Report in English with a French summary (KCE reports 176B)

publicité
KCE REPORT 176B
DÉPIS
STAGE DU CAN
NCER DU SEIN
N ENTRE 70 ET
T 74 ANS
2012
www.kce.fgo
ov.be
Le Centre fédéral d’ex
xpertise des
s soins de sa
anté
Le Ce
entre fédéral d’e
expertise des so
oins de santé es
st un parastatal, créé par la loi-p
programme (1) du
d 24
décem
mbre 2002 (articles 259 à 281), sous
s
tutelle du Ministre
M
de la San
nté publique et d
des Affaires sociales.
Il est chargé de réalis
ser des études éclairant
é
la décis
sion politique da
ans le domaine d
des soins de san
nté et
de l’a
assurance malad
die.
Conseil d’a
administratio
on
dent
Présid
Foncttionnaire dirigeantt de l'INAMI (vice président)
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dent du SPF Santté publique (vice président)
p
Présid
dent du SPF Sécu
urité sociale (vice président)
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nistrateur général de l'AFMPS
Repré
ésentants du minis
stre de la Santé publique
p
Repré
ésentants du minis
stre des Affaires sociales
s
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ésentants du Cons
seil des ministres
Agenc
ce intermutualiste
e
Organ
nisations professio
onnelles représen
ntatives
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m
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nisations professio
onnelles représen
ntatives
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nfirmiers
Fédérrations hospitalièrres
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mbre des Représentants
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embres effectifs
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erre Gillet
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avier De Cuyper
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ernard Lange
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arco Schetgen
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aniel Devos
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chiel Callens
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atrick Verertbrugge
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avier Brenez
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Jea
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yriam Hubinon
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han Pauwels
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aul Palsterman
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eve Wierinck
Membres suppléants
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Decoster
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ertels
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ois Perl
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Vermeyen
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ert Stamatakis
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oghe
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eels
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cteur Général
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oint
Direc
cteurs du program
mme d'études
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af Mertens
Je
ean-Pierre Closon
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hristian Léonard
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Contact
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ertise des Soins de
e Santé (KCE)
e
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evard du Jardin Botanique, 55
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@kce.fgov.be
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e
KCE REPORT 176B
GOOD CLINICA
AL PRACTICE
DEPIS
STAGE D
DU CAN
NCER DU
D SEIN
N ENTRE 70 ET
T 74 ANS
FRANÇOISE MAMBOURG,
M
JO R
ROBAYS, SOPHIIE GERKENS
2012
www.kce.fgo
ov.be
COLOPHO
ON
Titre:
d sein entre 70 et
e 74 ans
Dépistage du cancer du
Auteurs:
s (KCE), Sophie Gerkens
G
(KCE)
Françoise Mambourg (KCE), Jo Robays
Relecture:
heer (KCE), Nancy
y Thiry (KCE)
Frank Hulstaert (KCE)), Pascale Jonckh
Experts externe
es:
Marc
c Arbijn (WIV - IS
SP), Martine Berliière (UCL Saint-L
Luc), Hilde Bosmans (UZ Leuven)), Jean-Benoit Bu
urrion
(ASB
BL Brummammo)), Joëlle Desreux
x (CHU Liège), André-Robert
A
Griv
vegnée (Institut JJules Bordet), Pa
atrick
Neve
en (UZ Leuven), Myriam
M
Provost (S
SSMG), Hubert Th
hierens (UGent), Reinhilde
R
Van Ee
eckhoudt (WVG), Anne
A
Vand
denbroucke (UCL Saint-Luc), Geertt Villeirs (UZ Gentt).
Validateurs exte
ernes:
Philip
ppe Autier (IPRI-L
Lyon), Geert Page
e (Jan Yperman Ziekenhuis),
Z
Chanttal Van Ongeval ((KU Leuven)
Conflits d’intérê
êt:
Aucu
un conflit déclaré
Layout:
Ine Verhulst
V
Disclaimer:
• Le
es experts exterrnes ont été con
nsultés sur une version
v
(prélimin
naire) du rapporrt scientifique. Leurs
L
re
emarques ont été
é discutées au cours des réunion
ns. Ils ne sont pa
as co-auteurs du
u rapport scientiffique
ett n’étaient pas né
écessairement d’accord
d
avec son contenu.
• Une version (fina
ale) a ensuite étté soumise aux
x validateurs. La
a validation du rrapport résulte d’un
co
onsensus ou d’u
un vote majorita
aire entre les validateurs. Les va
alidateurs ne son
nt pas co-auteurrs du
ra
apport scientifiqu
ue et ils n’étaient pas nécessaire
ement tous les trrois d’accord ave
ec son contenu.
• Finalement, ce rap
pport a été appro
ouvé à l'unanimité par le Conseill d’administration.
• Le
e KCE reste seu
ul responsable des erreurs ou om
missions qui pourraient subsiste
er de même que
e des
re
ecommandations
s faites aux autorités publiques.
Date de publica
ation:
26 ap
pril 2012
Domaine:
Good
d Clinical Practice
e (GCP)
MeSH:
Breast Neoplasms ; Mammography
M
; Mass Screening
Classification NLM:
N
WP 870
8 - Breast - Neo
oplasms
Langue:
franç
çais, anglais
Format:
Adob
be® PDF™ (A4)
Dépot légal:
D/2012/10.273/19
Copyright:
Les rapports
r
KCE son
nt publiés sous Lic
cence Creative Co
ommons «by/nc/nd»
http:///kce.fgov.be/fr/co
ontent/a-propos-du
u-copyright-des-ra
apports-kce
Comment citer ce rapport?
Mam
mbourg F, Robays
s J, Gerkens S. Dépistage
D
du can
ncer du sein entre
e 70 et 74 ans. G
Good Clinical Pra
actice
(GCP
P). Bruxelles: Centre Fédérale d’Expertise des Soins de Santté (KCE). 2012. KCE Report 176B.
D/2012/10.273/19.
Ce document est disponible en télécharrgement sur le site Web du Centre fédéral d’expertisse des soins de sa
anté.
KCE Report 176
6B
„ PRÉF
FACE
Dé
épistage du cancerr du sein
i
Faire des choix
c
en matière de
d soins ressemb
ble vite à de la dis
scrimination, en particulier
p
lorsque ces choix sont ba
asés
sur l’âge. Comment
C
par exe
emple justifier le refus
r
de rembourrsement d’une inttervention coûteusse sur le cœur à une
personne, uniquement
u
sur un critère d’âge, même
m
si pour le re
este cette personn
ne est encore en bonne forme? De
e tels
raisonneme
ents conduisent sy
ystématiquement à des discussion
ns enflammées, no
ourries à partir de
e systèmes de valleurs
parfois diam
métralement oppo
osés.
La présente
e étude qui pose la question de sa
avoir s’il faut offrirr un dépistage orrganisé du cancerr du sein aux fem
mmes
âgées de 70
7 à 74 ans, nou
us place donc à nouveau sur un sol glissant. Mais
s il y a encore d’autres raisons d’être
d
particulièrement vigilants surr un tel sujet. Com
mme dans tout dé
épistage organisé
é, on s’adresse en
n effet à des gens
s qui
ne présente
ent a priori pas de
e plainte de santé
é et qui n’étaient donc
d
pas nécessa
airement demandeurs d’un tel exam
men.
L’adage priimum non nocere est donc ici d’auttant plus importan
nt.
En matière d’argumentation à développer, il y a aussi un défi particulier
p
à releve
er. Le clinicien est plus coutumier de
d la
logique utilisée pour poser un diagnostic che
ez une personne
e qui a une plaintte que de celle u
utilisée en matière
e de
screening. Dans le premierr cas, le risque d’un
d
résultat faux
x positif est non seulement plus petit mais est aussi
a
clairement considéré comme moins importan
nt qu’un résultat faux
f
négatif, qui équivaut à loupe
er un diagnostic. Cela
explique po
ourquoi les inconv
vénients d’un dép
pistage sont systématiquement sou
us évalués. De plu
us, le sujet est loin de
laisser l’opiinion publique ind
différente, un lobb
bying intense estt organisé à son propos, et il est (donc) aussi sensible
politiqueme
ent.
Même si on
n mobilise toutes les preuves scien
ntifiques disponib
bles pour fonder un
u avis sur la que
estion, on ne peutt pas
pour autant espérer arrêter la controverse. Nous
N
osons néan
nmoins espérer que ce rapport ap
pportera tout ce qu’on
q
peut attend
dre d’un organe d’avis scientifique dans
d
un tel débat.
Jean-Pierre
e CLOSON
Directeur Général
G
Adjoint
Raf MERTENS
Directeur Gén
néral
ii
„ RÉSU
UMÉ
Dé
épistage du cancerr du sein
KCE Report 176B
1
INTRODUC
CTION
Ce travail fait parttie d’un projet plu
C
us large ayant pour objet la mise à jour
d rapport: «Dépis
du
stage du cancer du sein», publié en 2005 (rapport KCE
n
n°11).
Il concerne
e plus particulièrem
ment l’extension du dépistage organisé
a
aux
femmes âgées de 70 à 74 ans qui ne préssentent par ailleu
urs ni
s
symptôme
évocate
eur, ni facteur de risque particulier.
L dépistage du cancer
Le
c
du sein es
st un processus ccomplexe qui com
mporte
d
des
bénéfices ett des risques. Les
L
principaux b
bénéfices attendu
us du
d
dépistage
du cancer du sein sontt la diminution de
e la mortalité et de la
m
morbidité
liées à la maladie. La diiminution de morrbidité implique so
oit un
a
allègement
des traitements,
t
soit une diminution d
des récidives ou
u des
s
stades
métastatiqu
ues de la maladie
e.
L risques principaux liés au dép
Les
pistage concernen
nt la qualité de vie. En
e
effet,
un résultat faussement pos
sitif, un diagnosttic excédentaire (surd
diagnostic)
suivi d’un traitement et l’avance au diagnostic (ou lead time, qui
e la durée par la
est
aquelle le diagnos
stic par dépistage
e précède le diagn
nostic
c
clinique)
ont des conséquences
c
surr la qualité de vie.
L
Les
résultats faussement positifs ont pour consé
équence d’inclure
e des
fe
emmes en bonne santé dans un circuit d’exxamens diagnosttiques
a
anxiogènes
voire invasifs
i
(biopsies)).
L sur-diagnostic peut être défini comme
Le
c
la détection de cas de cancers
q n’auraient jamais été perçus clin
qui
niquement en l’ab
bsence de dépista
age. Il
s
s’accroit
au fur et à mesure de la diminution de l’e
espérance de vie de la
p
population
dépistée. Le sur-traite
ement est une cconséquence du surd
diagnostic.
Vu qu’il est actuellemen
nt impossible de p
prédire si un canc
cer va
s développer, la
se
a très grande ma
ajorité des cance
ers diagnostiqués sont
trraités.
E
Enfin,
le dépistage
e met les cancers
s en évidence deu
ux ou trois ans plus tôt
q
que
ne le ferait un
u diagnostic clin
nique. Ceci implique que la pers
sonne
d
devient
«malade du
d cancer» et reço
oit des traitementss invasifs plus tôt dans
le
e décours de sa vie.
v
KCE Report 176
6B
Dé
épistage du cancerr du sein
QUESTIO
ONS POSÉES
Ce rapport inv
vestigue la question suivante: fau
ut-il étendre le dé
épistage
organisé du can
ncer du sein aux ffemmes âgées de
e 70 à 74 ans?
Si la réponse à cette question est négative, une
e question subsid
diaire se
pose: que répo
ondre à la personn
ne de cette tranch
he d’âge qui demande un
dépistage?
R
RÉSULTAT
TS ISSUS DE
D LA LITT
TÉRATURE
E
M
Mortalité
Les résultats des
L
s différents essais
s contrôlés rando
omisés permettent de
m
mettre
en évidence les faits suivantts:
•
MÉTHOD
DOLOGIE
L’étude des bé
énéfices cliniquess du dépistage se
e base sur une revue de
littérature effecttuée dans OVID M
Medline, EMBASE
E, CDSR et DAR
RE. Cette
revue a inclus les articles publiés en Anglais, Allemand,
A
Néerlandais et
Français de jan
nvier 2004 à avril 2
2011.
L’évaluation du rapport bénéfices-risques de ce dépistage se base sur une
revue des étud
des de modélisattion recherchées dans Medline, Embase,
E
NHS EED et Econlit.
E
Cette revu
ue a inclus les arrticles publiés en Anglais,
Allemand, Néerrlandais et França
ais de janvier 2000
0 à septembre 20
011.
Afin de quantifiier le rapport bén
néfices-risques da
ans le contexte belge, un
modèle a été construit dans cce but. La consttruction de ce modèle
m
a
nécessité de rechercher dans Medline, Embase
e, HTA EED et Psycinfo
P
(1950-10/2011)) les études relativves à la qualité de vie pendant et après le
dépistage et le
e traitement du cancer du sein.. Le modèle con
ntient le
maximum de do
onnées belges utiilisables.
Enfin, des reco
ommandations de
e bonne pratique
e ont été rédigée
es sur la
base des élé
éments de pre
euve obtenus. Une révision desdites
d
recommandatio
ons a été effectué
ée par les expertts externes. Aucu
un conflit
d’intérêts n’a étté signalé.
iii
minution de morttalité de 23% sur une
Le dépistage entraîne une dim
uivi de 13 ans che
ez les femmes de
e plus de 50 ans ayant
période de su
bénéficié d’un
n dépistage tous le
es deux ans.
•
Cette diminuttion de mortalité se
s manifeste entrre 4 et 7 ans aprrès le
dépistage. Il convient donc de la mettre en perspective avec
l’espérance de vie moyenne de ce groupe d’âg
ge qui est de 16 ans
a à
70 ans et de 13
1 ans à 74 ans (d
données belges d
de 2009).
D
Dans
l’interprétatio
on des études inte
ernationales, il fau
ut tenir compte du
u petit
n
nombre
de particip
pantes âgées de 70
7 à 74 ans; consséquemment, l’effe
et sur
la
a mortalité n’a pu être statistiqueme
ent démontré pou
ur celles-ci.
M
Morbidité
Outre le gain en années
O
a
de vie, le principal
p
avantage
e attendu du dépistage
e de permettre des traitements moins
est
m
agressifs, vvu que le dépista
age a
p
pour
objectif de mettre
m
en éviden
nce des petites tumeurs. Les don
nnées
b
belges
dont nous
s disposons actu
uellement ne nou
us permettent pa
as de
v
valider
cette assertion. Les donnée
es les plus récentes (rapport KCE 150)
fo
ont état de 58% de
d chirurgie cons
servatrice versus 38% de mastecto
omies
to
otales dans les sttades les moins avancés
a
(Stades I and II). Près de
e 90%
d
des
bénéficiaires de la chirurgie conservatrice reççoivent égalemen
nt un
trraitement par rad
diothérapie, 38% d’entre
d
elles reço
oivent un traiteme
ent de
c
chimiothérapie
néo
o-adjuvante et 41% un traitement h
hormonal.
D
D’autre
part, les essais
e
contrôlés randomisés
r
n’ont quantifié ni le tau
ux de
ré
écidives ni l’évolu
ution vers les stades métastatique
es de la maladie. Il est
d
donc
impossible d’infirmer
d
ou de co
onfirmer l’hypothè
èse d’une réductio
on de
m
morbidité
sur cette
e base. Par contrre, la perte de qu
ualité de vie impu
utable
a métastases es
aux
st inclue dans le modèle
m
(voir ci-de
essous).
iv
Dé
épistage du cancerr du sein
ÉTUDES DE MODÉ
ÉLISATION
Les principales études de modé
élisation ont été ré
éalisées au sein du
d projet
CISNET (Canc
cer Intervention a
and Surveillance Modeling Network). Ces
modèles avaie
ent pour objectiif d’évaluer la contribution rela
ative du
dépistage par mammographie
m
ett du traitement adjuvant sur la rédu
uction de
la mortalité due
e au cancer du sein observée au
ux Etats-Unis de 1975 à
2000, et ils uttilisent les donné
ées issues du Breast
B
Cancer Sc
creening
Consortium.
Les résultats de
e ces modèles ind
diquent un gain en années de vie allant
a
de
9 à 22 ans parr 1.000 femmes d
dépistées. D’autre
es modèles n’utilis
sant pas
la méthodolog
gie CISNET son
nt également décrits
d
dans le rapport
scientifique.
Ces modèles ne
n sont pas adapttables en tant que
e tels à la situatio
on belge
car il est impos
ssible d’y inclure les données belg
ges. Un nouveau modèle
spécifique a donc été construit.
UN MODÈ
ÈLE DE CO
OHORTE POUR
P
LA
BELGIQU
UE
Méthodologie
e
Le modèle construit pour ce rap
pport est un modè
èle de cohorte qu
ui évolue
par cycles annuels. Il compare deux cohortes th
héoriques de fem
mmes de
plus de 70 ans
s, l’une sans inviitation au dépista
age (situation actuelle) et
l’autre où les fe
emmes continuen
nt à être invitées au dépistage. Le taux de
participation et la répartition dess cancers détectés
s par le dépistage
e versus
les cancers d’in
ntervalle sont conssidérés comme étant les mêmes que
q dans
la tranche d’âge
e 50-69 ans.
Le dépistage a pour objectif de m
mettre en évidenc
ce les tumeurs à un
u stade
précoce (I et II) afin d’évite
er l’évolution ve
ers le stade IV
V (stade
métastatique) qui
q est incurable. Ce «stage-shift» implique que parmi tous
les cancers dép
pistés, la proportio
on des stades pré
écoces (I, II) augm
mente en
même temps que
q
la proportion
n des stades ava
ancés (II et IV) diminue.
d
D’autre part, nous avons émis l’hypothèse selon
n laquelle la surv
vie et la
qualité de vie dépendent
d
de l’âg
ge de la patiente et
e du stade de la tumeur.
Elle ne tient pa
as compte du fait que le pronostic des
d cancers déte
ectés par
KCE Report 176B
1
le
e dépistage est meilleur que cellui des cancers détectés clinique
ement
(c
cancers d’interva
alle et cancers survenant che
ez les femmes nonp
participantes).
P
Paramètres
Ce modèle explloite au maximu
C
um les données belges, à sa
avoir :
l’espérance de vie moyenne des
s femmes selon leur âge (2009)), les
d
données
du regis
stre du cancer (C
Communauté Fla
amande), les don
nnées
is
ssues du progra
amme de dépis
stage actuel (50
0-69 ans), le temps
n
nécessaire
pour infirmer un dia
agnostic faussem
ment positif (Ag
gence
In
ntermutualiste, AIIM/IMA) et les do
onnées de survie à cinq ans en fon
nction
d stade (Registre
du
e du Cancer). Les données de la Communauté Flam
mande
o été privilégiées
ont
s car elles sont pllus complètes et p
parce que le dépistage
o
opportuniste
après
s 70 ans y est mo
oins fréquent que dans le reste du pays.
L durée de l’avan
La
nce au diagnostic et le pourcentage
e de sur-diagnosttic ont
é estimées au dé
été
épart de l’analyse
e de la littérature.
M
Mesure
de la qualité de vie
Les données sur la qualité de vie
L
e pendant le dépistage et le traite
ement
p
proviennent
de la littérature. L’instrrument utilisé pou
ur décrire les éta
ats de
s
santé
est l’EQ-5
5D (European Quality of Life--5 Dimensions); ces
d
descriptions
ont été
é valorisées parr la population gé
énérale anglaise («UK
ta
ariffs»). Nous ne
e disposons pas de données rela
atives à la population
b
belge.
L variations de la qualité de vie des
Les
d femmes de plus de 70 ans utillisées
d
dans
le modèles sont
s
les suivantes:
•
•
La perte de qualité de vie co
onsécutive à un résultat de dépistage
faussement positif est estimée à 16% pendant 4
45 jours.
entes cancéreuses et pendant la première année qu
ui suit
Pour les patie
le diagnostic (quel
(
que soit le traitement)
t
la pertte de qualité de vie est
estimée à 16% pour les stade
es I, II, III et à 18
8% pour les stade
es IV.
Pendant les années
a
suivantes, la perte de qualitté de vie est estim
mée à
6% pour les stades I, II, III. Cette
C
perte demeu
ure stationnaire (18%)
(
pour les stade
es IV.
P
Plusieurs
limitatio
ons de cette app
proche nous oblig
gent à interpréter ces
c
chiffres
avec préca
aution
KCE Report 176
6B
Dé
épistage du cancerr du sein
Résultats
Le scénario de
d base montre que le dépistag
ge entre 70 et 74 ans
permettrait d’év
viter 1,3 décès po
our 1000 femmes
s qui y participentt, ce qui
représente une
e réduction de 2
21% des décès. Globalement, le nombre
d’années de vie
e sauvées est estiimé à 13,1 et le gain en QALY à 3,9.
Etant donné qu
u’il existe une inccertitude importan
nte (pour les déta
ails, voir
les discussions
s dans le rapport scientifique) au sujet
s
des ces estim
mations,
une analyse de
d sensibilité du
u modèle a été réalisée. Cette analyse
comprend un sc
cénario pessimistte et un scénario optimiste.
o
Le scenario pe
essimiste fait l’hyypothèse d’un ex
xcédent de diagnostic de
20%, d’un taux de faux positifs d
de 10%, entrainan
nt une perte de qu
ualité de
vie de 0,19 perd
durant pendant 54
4 jours (temps né
écessaire pour infiirmer les
résultats). La distribution des cancers dépisté
és par stades observée
o
actuellement da
ans le cadre du d
dépistage organisé en Flandre (50--69 ans)
a été appliqué
ée au groupe d
dépisté. Ce scén
nario pessimiste permet
d’estimer un ga
ain de 8,7 année
es de vie et une perte de 3,1 QA
ALY pour
1000 femmes participant au dé
épistage. Ceci sig
gnifie que dans certaines
c
circonstances, au demeurant ttout à fait réalisttes, le dépistage
e puisse
aboutir à une pe
erte en terme de q
qualité de vie.
Le scenario optimiste fait l’hypotthèse d’un excédent de diagnostic
c de 3%,
d’un taux de faux positifs de 2%
%, entrainant une perte
p
de qualité de
d vie de
0,13 perdurant pendant 36 jourss. Ce scénario ap
pplique au groupe
e dépisté
la distribution par stades obsservée actuellem
ment dans le ca
adre du
dépistage orga
anisé aux Pays-B
Bas (70-74 ans)). Ce scénario optimiste
o
permet d’estime
er un gain de 17,0 années de vie et un gain de 16,,3 QALY
pour 1000 fem
mmes participant au dépistage. Ceci signifie qu’’il serait
nécessaire d’inv
viter 67 femmes à participer au dé
épistage pendant cinq
c
ans
pour gagner un QALY.
v
C
CONCLUS
ION
Le dépistage estt organisé dans le but d’améliorrer le bien-être de
L
d la
p
population
en évitant notamment des décès prématu
urés. Il est certain
n que
p
prolonger
le dépistage jusqu’à l’âge
e de 74 ans devra
ait permettre de ga
agner
q
quelques
années de vie pour un certain nombre d
de femmes. Touttefois,
l’influence d’un dé
épistage organisé sur la qualité de vie est nettement plus
a
aléatoire
(niveau de
d preuve très faible car basé sur u
un modèle). Selon des
h
hypothèses
raison
nnables, cette inte
ervention pourrait même aboutir à une
p
perte
en terme de
e qualité de vie. Dans
D
ces condition
ns, il se pourrait que
q la
b
balance
bénéfices
s-risques de ce dépistage
d
penche
e du côté d’une perte
g
globale
de bien-ê
être de la population. Il n’est do
onc pas recomm
mandé
d
d’étendre
le dépis
stage organisé du
u cancer du sein a
aux femmes âgée
es de
7 à 74 ans.
70
vi
Dé
épistage du cancerr du sein
„ RECO
OMMAND
DATIONS
Sa
a
KCE Report 176B
1
•
L’invittation systématiique des femme
es âgées de 70 à 74 ans à parrticiper au dépis
stage
organisé du cancer du
u sein n’est pas recommandée.
r
•
Si une
e personne de plus de 70 ans demande une mammographie dans un objecttif de
dépisttage, il importe que
q le médecin veille
v
à ce qu’elle
e soit bien inform
mée des avantag
ges et
des in
nconvénients pottentiels de celle-ci.
•
Toute mammographie
e de dépistage doit répondre aux
x exigences euro
opéennes en ma
atière
de qualité, dont notam
mment : le contrrôle de la qualité
é des installation
ns, la double lec
cture,
l’enreg
gistrement et l’optimisation du taux de rappel. C’est pourrquoi, les méde
ecins
orienteront la personn
ne qui demande
e un dépistage vers
v
une structurre qui réponde à ces
exigen
nces de qualité.
•
Afin de
d minimiser le riisque de perte de qualité de vie lié aux résultats faussement pos
sitifs,
il impo
orte que le taux de rappel après mammographie
e soit le plus bas
s possible et res
ste en
desso
ous du seuil défin
ni par les critères
s européens (<5%
%).
Le KCE re
este seul responsab
ble des recommandations faites aux au
utorités publiques
KCE Report 176
6
S
Screening
Breast Cancer
C
1
„ TABL
LE OF CO
ONTENT
TS
LIST OF FIGURES
S ................................................................................................................................................. 4
LIST OF TABLES ................................................................................................................................................... 4
LIST OF ABBREVIIATIONS ................................................................................................................................... 5
„
1.
2.
3.
SYNTHÈS
SE .............................................................................................................................................. 7
CONTEXT
TE .............................................................................................................................................. 7
QUESTIONS POSÉES ............................................................................................................................. 7
DESCRIPT
TION DE LA PRO
OBLÉMATIQUE ........................................................................................... 8
3.1.
APPROCH
HE INTUITIVE ........................................................................................................................... 8
3.2.
APPROCH
HE ÉPIDÉMIOLOGIQUE ......................................................................................................... 8
3.2.1. Objectif
O
à court terrme ................................................................................................................ 9
3.2.2. Objectif
O
ultime............................................................................................................................. 9
3.2.3. Faux
F
positifs et dia
agnostics excéden
ntaires ............................................................................... 9
MÉTHODO
OLOGIE .................................................................................................................................. 11
4.
4.1.
ESTIMATIION DES BÉNÉFICES DU DÉPIST
TAGE ............................................................................... 11
4.1.1. Diminution
D
de la mortalité
m
........................................................................................................ 11
4.1.2. Amélioration
A
de la qualité de vie des
s patientes ....................................................................... 11
4.2.
ESTIMATIION DES INCONV
VÉNIENTS DU DÉPISTAGE...................................................................... 11
4.2.1. Diminution
D
de la qu
ualité de vie des participantes
p
.................................................................... 11
4.3.
APPROCH
HE PAR MODÉLISATION ...................................................................................................... 12
4.3.1. Mesures
M
de la qua
alité de la vie................................................................................................ 12
4.3.2. Description
D
du mod
dèle ............................................................................................................ 12
4.3.3. Hypothèses
H
de bas
se................................................................................................................ 14
4.3.4. Alimentation
A
du mo
odèle ........................................................................................................... 14
4.3.5. Analyse
A
de sensibilité .............................................................................................................. 14
RÉSULTA
ATS .......................................................................................................................................... 15
DISCUSSION ......................................................................................................................................... 15
5.
6.
2
S
Screening
Breast Cancer
C
KCE Reportt 176
6.1.
AJOUTER
R DES ANNÉES À LA VIE ? ................................................................................................... 15
6.2.
7.
AJOUTER
R DE LA (QUALITÉ DE) VIE AUX ANNÉES
A
? ....................................................................... 16
6.2.1. Traitements
T
moins
s agressifs? ................................................................................................. 16
6.2.2. Faux
F
positifs ............................................................................................................................. 16
6.2.3. Excès
E
de diagnosttics et de traiteme
ents................................................................................... 16
CONCLUS
SIONS ..................................................................................................................................... 16
7.1.
FAUT-IL PROLONGER
P
LE DÉPISTAGE JUS
SQU’À L’ÂGE DE 74 ANS ? .......................................... 16
7.2.
QUE REPONDRE A LA PE
ERSONNE QUI DE
EMANDE UN DEP
PISTAGE? .......................................... 17
7.3.
8.
MESSAGE
E CLÉ ...................................................................................................................................... 17
RÉFÉREN
NCES ....................................................................................................................................... 18
„
1.
SCIENTIF
FIC REPORT ............................................................................................................................ 19
INTRODUCTION .................................................................................................................................... 19
1.1.
CONTEXT
T OF THIS REPORT .............................................................................................................. 19
1.2.
SCOPE OF
O THIS REPORT
T ................................................................................................................... 19
1.3.
BREAST CANCER
C
SCREE
ENING IN BELGIU
UM.................................................................................... 19
1.4.
CLINICAL QUESTIONS ......................................................................................................................... 20
1.5.
2.
SCIENTIF
FIC APPROACH ...................................................................................................................... 20
LITERATU
URE REVIEWS ....................................................................................................................... 21
2.1.
REVIEW OF
O CLINICAL STU
UDIES......................................................................................................... 21
2.1.1. Methodology
M
............................................................................................................................. 21
2.1.2. Description
D
of scre
eening benefit .............................................................................................. 22
2.1.3. Description
D
of scre
eening harms............................................................................................... 25
2.1.4. Screening
S
conditio
ons ............................................................................................................... 27
2.1.5. Key
K data ................................................................................................................................... 28
2.1.6. Conclusion
C
................................................................................................................................ 29
2.2.
REVIEW OF
O MODELING STUDIES
S
...................................................................................................... 29
2.2.1. Literature
L
search strategy
s
....................................................................................................... 29
2.2.2. Selection
S
criteria ....................................................................................................................... 29
KCE Report 176
6
S
Screening
Breast Cancer
C
2.2.3.
2.2.4.
2.2.5.
2.3.
3
Quantity of researc
Q
ch available ................................................................................................. 30
S
Selected
studies ....................................................................................................................... 30
C
Conclusion
................................................................................................................................ 33
3.
REVIEW OF
O QUALITY OF LIFE STUDIES ........................................................................................... 33
2.3.1. Methods
M
.................................................................................................................................... 34
2.3.2. Results
R
..................................................................................................................................... 35
2.3.3. Discussion
D
................................................................................................................................ 43
DECISION
N ANALYSIS ........................................................................................................................... 43
3.1.
DATA SOU
URCES ................................................................................................................................... 44
3.2.
MODEL DESCRIPTION
D
......................................................................................................................... 44
3.3.
DESCRIPT
TION OF THE PA
ARAMETERS .............................................................................................. 48
3.3.1. Age
A specific overa
all survival .................................................................................................... 48
3.3.2. Breast
B
cancer incid
dence .......................................................................................................... 48
3.3.3. Participation
P
rate ...................................................................................................................... 48
3.3.4. Proportion
P
of scree
en detected breas
st cancers ........................................................................ 48
3.3.5. Recall
R
rate ................................................................................................................................ 48
3.3.6. Stage
S
distribution and
a stage shift ............................................................................................ 49
3.3.7. Stage
S
specific rela
ative survival ................................................................................................ 50
3.3.8. QALY
Q
........................................................................................................................................ 51
3.4.
RESULTS
S ............................................................................................................................................... 54
3.5.
4.
DISCUSSION ......................................................................................................................................... 58
ANSWER TO CLINICAL QUESTIONS
Q
................................................................................................. 60
4.1.
BREAST CANCER
C
RELATE
ED MORTALITY ......................................................................................... 60
4.2.
DELAY BE
ETWEEN THE SC
CREENING AND THE
T
MORTALITY
Y REDUCTION ................................... 60
4.3.
OVERALL
L MORTALITY ......................................................................................................................... 60
4.4.
MORBIDIT
TY ............................................................................................................................................ 60
4.5.
FALSE PO
OSITIVE OR FALS
SE NEGATIVE RESULTS .......................................................................... 60
4.6.
ADDITION
NAL DIAGNOSTIC
C TESTS ..................................................................................................... 60
4.7.
OVER-DIA
AGNOSIS AND OVER-TREATMEN
O
NT .................................................................................... 60
4
S
Screening
Breast Cancer
C
4.8.
5.
LIST OF FIGURES
F
LIST OF TABLES
T
KCE Reportt 176
WHAT AT
TTITUDE SHOULD
D BE RECOMMENDED FOR WOM
MEN IN CASE OF
F SELF REFERRA
AL?61
REFEREN
NCES ....................................................................................................................................... 62
s
for which uttilities are needed
d (reflection process) ....................................................................
Figure 2.1: Health states
Figure 2.2: Percenttage change in utilities ..........................................................................................................................
Figure 3.1: Comparrison of the two co
ohorts with and without a screening
g program..........................................................
Figure 3.2: Comparrtments in the two
o cohorts and the transitions
t
betwee
en them ............................................................
Ta
able 2.1: Data issu
ued from clinical literature review ...................................................................................................
Ta
able 2.2: Selection
n criteria ...........................................................................................................................................
Ta
able 2.3: Modeling
g studies excluded
d after full-text ass
sessment .................................................................................
Ta
able 2.4: results of the different models
m
in terms of
o mortality reduc
ction and years o
of life gained perr 1000
wo
omen screened fo
or the different mo
odels .....................................................................................................................
Ta
able 2.5: Article se
election criteria .................................................................................................................................
Ta
able 2.6: Health sttates descriptions
s for the study of Lidgren
L
et al. .............................................................................
Ta
able 2.7: Description of a “false pos
sitive” state (Gerard et al)83..................................................................................
Ta
able 2.8: Description of the selected
d utilities ..............................................................................................................
Ta
able 3.1: Stage diistribution among screen detected breast cancers, interval cancers a
and cancers amon
ng non
pa
articipants, age 50
0-69, Flemish scre
eening program 2001-2006. ................................................................................
Ta
able 3.2: Parametters used in the model
m
.....................................................................................................................
Ta
able 3.3 Modeling results: baseline, worst and best case
c
scenario. ..........................................................................
Ta
able 3.4 Modeling results: sensitivitty analysis. ...........................................................................................................
KCE Report 176
6
LIST OF ABBREVIA
A
ATIONS
S
Screening
Breast Cancer
C
AB
BBREVIATION
DEFINITION
CP
PG
CC
CRT
CII
DC
CIS
DE
ET
BC
CSC
AH
HRQ
BC
CR
DN
NETB
CIISNET
IM
MA/AIM
IN
NAMI/RIZIV
IC
CER
KC
CE
MST
M-A
NIIS
NB
BSS
NB
BCSP
NH
HS
NH
HS EED
NC
CI
QA
ALY
Qo
oL
RC
CT
RR
R
ce Guideline
Clinical Practic
Cochrane Cen
ntral Register of Controlled
C
Trials
Confidence Intterval
Ductal Carcino
oma in situ
Data Extractio
on Table
Breast Cancerr Surveillance Con
nsortium (USA)
Agency for He
ealth Care Researrch and Quality
Belgian Cance
er Registry
Dutch Nationa
al Evaluation Team
m for Breast cance
er screening
Cancer Interve
ention and Surveillance Modelling Network
N
Intermutualistic Agency
National Institu
ute for Health and
d Disability Insuran
nce
Incremental co
ost-effectiveness ratio
r
Belgian Health
hcare Knowledge Centre
Mean Sojourn Time
Meta-analysis
National Institu
ute for Statistics
Canadian Natiional Breast Canc
cer Screening Study
Norwegian Bre
east Cancer Scree
ening Programme
es
National Healtth Service (UK)
NHS Economic Evaluation Data
abase
National Canc
cer Institute (USA))
Quality Adjuste
ed Life Year
Quality of Life
Randomized Controlled
C
Trial
Relative Risk
5
6
S
Screening
Breast Cancer
C
SE
EER
SR
R
ST
T
TT
TO
UK
K
US
SA
US
SPSTF
Surveillance, Epidemiology
E
and
d End Results (US
SA)
Systematic Re
eview
Sojourn Time
Time-trade-offf
United Kingdo
om
Unites States of America
US Preventive
e Services Task Force
KCE Reportt 176
KCE Report 176
6
„ SYNT
THÈSE
Screening Breast Cancer
C
7
1 CONTEX
1.
XTE
Le KCE a déjà publié trois rapports
L
s sur le dépistage du cancer du sein. Le
ra
apport de base publié en 2005 (rapport N°11 du KCE) concernait le
d
dépistage
du canc
cer du sein en gé
énéral, dans la po
opulation sans fac
cteurs
d risque. Le dépistage du cancer du
de
d sein des femm
mes de la tranche d’âge
4
40-49
ans a fait l’o
objet d’une mise à jour partielle pub
bliée en 2010. Dans ce
ra
apport (rapport N° 129 du KCE
E), le KCE ne recommandait pa
as le
d
dépistage
systématique des femm
mes de moins de 50 ans. Le trois
sième
ra
apport (rapport 172
1
du KCE), pu
ublié en 2012, a posé le problèm
me de
l’indentification de
es femmes expos
sées à un risque
e accru de cance
er du
s
sein.
Le rapport actuel pose la question de l’exxtension du dépistage
o
organisé
du cance
er du sein aux fem
mmes âgées de 70
0 à 74 ans
C
Cette
question es
st régulièrement adressée aux po
oliticiens en raiso
on de
l’augmentation rég
gulière de l’espérrance de vie de la population féminine.
S la plupart des
Si
s groupes actifs dans le dépista
age demandent cette
p
prolongation,
les autorités publiqu
ues font preuve d
de moins d’unanimité.
S
Seuls
quatre Etatts membres de l’Union européen
nne ciblent la tra
anche
d
d’âge
des 70-74 (la France, les Pays-Bas,
P
l’Espag
gne et la Suède)1. Les
a
autres
pays insiste
ent sur la nécessité d’informer les ffemmes et de parrtager
a
avec
elles la prise de décision.
2 QUESTIIONS POSÉ
2.
ÉES
Le dépistage orga
L
anisé du cancer du sein devrait-il être prolongé jusqu’à
l’âge de 74 ans? Si
S la réponse à ce
ette question est n
négative, que répo
ondre
à la personne qui demande
d
ce dépistage?
L première questtion concerne plus
La
s spécifiquement les pouvoirs publlics et
la
a seconde, les pre
estataires de soin
ns.
8
S
Screening
Breast Cancer
C
3. DESCRIPTION D
DE LA PRO
OBLÉMATIQ
QUE
3.1. Approche intuitive
De façon intuittive, le dépistage
e du cancer fait sens. Les médias sont
généralement enthousiastes
e
à ll’égard du dépista
age. Cette attitud
de a été
démontrée par Schwartz au dé
ébut du 21e siècle
e2. Une enquête réalisée
onsidéraient que dépister
aux Etats-Unis a révélé que 87% des adultes co
des personnes intterrogées déclara
aient que
est une bonne idée. Trois quart d
u cancer à un sstade précoce sa
auve la vie la plu
upart du
diagnostiquer un
temps. L’enthousiasme des rép
pondants était si fort que pour la majorité
sion à prendre mais
m
un
d’entre eux le dépistage n’était pas une décis
impératif moral3.
Cette attitude générale que no
ous pouvons rés
sumer ainsi “la détection
d
c
sauve de
es vies” peut av
voir suscité des attentes
précoce des cancers
irréalistes de la
l part des femm
mes. Silverman a réalisé des interviews
téléphoniques pour
p
évaluer comment les femmes considèrent le ca
ancer du
sein et le bénéfice du dépistag
ge par mammographie4. La majo
orité des
c
le ccancer du sein comme une maladie
répondantes considérait
progressive un
niforme et croyaitt que tous les ca
ancers débutent par une
forme curable et
e silencieuse. En
n résumé, ces fem
mmes pensaient que
q si le
cancer du sein n'est pas détecté
é par une mammo
ographie et traité de
d façon
andit, se propage
e et tue. Fortes
s de ces croyances, les
précoce, il gra
femmes estima
aient que les canccers avancés (et sans
s
doute la plupart des
cancers mortels
s) sont liés à un é
échec au niveau du dépistage préco
oce.
Schwartz a sou
uligné que 94% de
es femmes ne sav
vent pas que le dé
épistage
peut détecter des
d cancers qui n
ne vont jamais progresser.
p
De plu
us, 92%
des répondante
es sont persuadé
ées du fait que la
a mammographie ne peut
faire de tort à une personne qui n
n'a pas de cancerr du sein5.
Le corps médical lui-même n’a
appréhende pas toujours le dépis
stage de
ue de nombreux cliniciens
c
restent focalisés
f
manière adéquate. C’est ainsi qu
sur le taux de cancers diagnosstiqués (objectif intermédiaire), allors que
d dépistage est de diminuer la mortalité.
m
D’autre part, les
l’objectif final du
cliniciens parais
ssent plus sensib
bilisés au risque de
d méconnaître un
n cancer
(faux négatif) qu’aux risques liés aux résultats faussement positifs.
KCE Reportt 176
3
3.2.
Approche épidémiologiq
que
Le cancer du sein est le cancer le plus fréquent chez la femme
L
e. En
B
Belgique,
10.849 cancers
c
du sein ont
o été diagnostiq
qués en 2008. Plu
us de
trrois quarts des ca
ancers du sein so
ont diagnostiqués après l’âge de 50
0 ans.
L
L’âge
moyen au moment du diag
gnostic est de 62
2 ans. L’incidenc
ce du
c
cancer
du sein estt de 370,7/100.00
00 dans le groupe des femmes âgées de
7 à 75 ans6.
70
N
Néanmoins,
la part relative de la mortalité
m
due au ccancer du sein da
ans la
m
mortalité
totale difffère en fonction de l’âge. En 1999, le cancer du sein
n était
re
esponsable de 18
8% des décès ch
hez les femmes â
âgées de 50 à 54
4 ans,
d 13% dans le groupe de 60 à 64
de
4 ans et de 6% dans le groupe de
e 70 à
7 ans (Rapport N°11 du KCE). En
74
E 2006, cette prroportion était de 14%
p
pour
les femmes âgées
â
de 50 à 54
4, 12% pour le grroupe de 60 à 64
4 ans,
7 pour le groupe
7%
e des 70 à 74 ans et 5% pour le gro
oupe des 75 à 79 ans6.
C
Caractéristiques
fo
ondamentales d’u
un dépistage:
1.
Le dépistage s’adresse à des personne
es en bonne santé
Contraireme
ent au patient qu
ui consulte son m
médecin en raiso
on d’
une plainte ou d’un symptô
ôme, la personn
ne qui participe à un
dépistage es
st présumée inde
emne de la malad
die recherchée.
2
2.
Le dépistage a pour objectif à court terme de cconfirmer l’absenc
ce de
la maladie.
3
3.
Le dépistage a pour objectif ultime
u
de diminuer la mortalité/morrbidité
liée à la maladie.
4
4.
Le principe “p
primum non nocere” est particulière
ement d’applicatio
on en
ce qui concerrne le dépistage.
Rappelons que pour
R
p
mille femme
es dépistées enttre 70 et 74 ans, plus
d 990 sont indem
de
mnes du cancer du sein.
KCE Report 176
6
S
Screening
Breast Cancer
C
9
3.2.1. Objecttif à court terme
3
3.2.3.
Faux pos
sitifs et diagnostiics excédentaire
es
Le dépistage a pour objectif de confirmer l’abs
sence de la mala
adie. La
personne qui participe au dépistage bénéfic
cie de la “prés
somption
n ce qui concerne
e le cancer du sein. A l’inverse, la patiente
d’innocence” en
qui consulte so
on médecin parce
e qu’elle a une plainte
p
ou parce qu’elle
q
a
constaté quelq
que chose d’inhabituel, devient “suspecte” de maladie.
m
L’objectif du médecin
m
et les mo
oyens à mettre en
e œuvre dans ces
c
deux
situations sont diamétralement o
opposés. Dans le
e cas d’une mise au point
e médecin a le de
evoir de tout mettre en œuvre pourr trouver
diagnostique, le
une étiologie à la plainte ou au symptôme. A l’in
nverse, dans le cadre
c
du
m
a le devoir de pratiquer uniquement
u
les examens
e
dépistage, le médecin
indispensables.. Ceci afin de min
nimiser les risque
es et les inconvén
nients du
dépistage pourr les 996 femmes (/1.000) qui sontt indemnes du ca
ancer du
sein.
d
médecins éttant essentiellement effectuée en
n hôpital
Le formation des
auprès de malades, ce change
ement de point de vue est franc
chement
our un clinicien.
contre-intuitif po
Avant d’instaurer un
A
u dépistage orga
anisé, il est nécesssaire de s’assure
er que
la
a balance avanta
ages/inconvénien
nts du dépistage penche du côté
é des
a
avantages.
Pour ce faire, l’ample
eur de la diminu
ution de mortalité
é doit
c
contrebalancer
la perte de qualité de
d vie consécutive
e aux inconvénients et
a risques induits
aux
s par le dépistage
e.
L
Les
résultats dits
s: “faux-positifs” (suspicion de lésion cancéreus
se en
d
dehors
de la prése
ence d’un cancer)) sont les effets négatifs indésirable
es du
d
dépistage
du canc
cer du sein les plus fréquents. Cess résultats fausse
ement
p
positifs
créent de
e hauts niveaux
x d'anxiété et so
ont suivis d’examens
c
complémentaires.
P
Plus
encore que le
es faux–positifs, le risque de diagn
nostic excédentairre est
le
e risque majeur du dépistage des femmes âgéess de 70 à 74 ans. Le
d
diagnostic
excéde
entaire peut se dé
éfinir comme le fa
ait de diagnostiquer un
c
cancer
dont l’évo
olution est telle qu’il ne se serait jamais manifesté
c
cliniquement
en l’a
absence de dépis
stage8. Ce risque est d’autant plus élevé
q
que
le cancer es
st d’évolution len
nte et que l’esp
pérance de vie de
d la
p
personne
est faib
ble. Ce risque est
e particulièreme
ent méconnu dans la
p
population.
Très peu de femmes savent en effet que certains cancers
é
évoluent
tellemen
nt lentement que
e même s'ils ne
e sont pas traité
és ils
n
n'altèreront
pas la santé9.
C rapport a pourr objectif de quanttifier les avantage
Ce
es et les inconvén
nients
(v
voir Figure 1) de ce dépistage afin de pouvoir les m
mettre en perspecttive et
s
s’assurer
que les bénéfices l'emporrtent largement su
ur les risques de perte
d qualité de vie.
de
3.2.2. Objecttif ultime
Diagnostiquer les cancers à un stade préco
oce avant qu’ils ne se
étastases) est l’h
hypothèse fondatrice du
développent ett essaiment (mé
dépistage du ca
ancer. C’est ainsi que l’on attend du
d dépistage qu’il diminue
la mortalité spé
écifique à la mala
adie et conséquem
mment la mortalitté totale.
Le fait que la technologie
t
utilisé
ée permette de diagnostiquer
d
des
s lésions
peu avancées et donc potentiellement curable
es ne représente
e qu’une
étape intermédiaire dans ce proccessus. Il s’agit d’une condition nécessaire
p suffisante7.
mais qui n’est pas
On peut égale
ement émettre l’’hypothèse que le dépistage réd
duise la
morbidité liée à la maladie, en p
permettant l’utilisation de traitementts moins
invasifs (maste
ectomies partielles plutôt que mas
stectomies totales
s) et en
évitant une parttie des évolutions vers les stades métastatiques.
m
10
S
Screening
Breast Cancer
C
KCE Reportt 176
Figure 1 mise en perspective d
des avantages ett des inconvénients potentiels du
u dépistage.
Faux-négaatif
Rééassurance
innadéquate
Résultat -
Rééassurance
Diagnostic retardé
r
Normal
Dépisttage par
mammo
ographie
Faux-possitif
Exxamens complémeentaires
Anormal
Résultat +
Canncer
invaasif
Caancer
inn situ
Traitement
précoce
Traitement
précoce Diminuttion
de mortaalité
Surtraittement
KCE Report 176
6
S
Screening
Breast Cancer
C
4. MÉTHODOLOGIE
Nous avons rec
cherché des élém
ments de réponse aux questions prrécitées,
dans la littératu
ure clinique, danss les études de modélisation et dans
d
les
données nation
nales et internatio
onales. Ces reche
erches ont été me
enées en
suivant les procédures en vigue
eur au KCE. Elles
s sont décrites en
n détails
e 2 du rapport scie
entifique.
dans le chapitre
4.1. Estimattion des bénéfices du dépista
age
4.1.1. Diminu
ution de la morta
alité
Les principales
s données proban
ntes relatives au dépistage du ca
ancer du
sein, sont issue
es de huit essaiss contrôlés rando
omisés. Sur base
e de ces
essais, on peutt retenir deux consstats principaux:
1. Le dépista
age entraîne une diminution de mortalité
m
de 23% sur une
période de
e suivi de 13 ans pour les femmes de plus de 50 an
ns ayant
bénéficié d’un
d
dépistage tou
us les deux ans.
2. Cette dimin
nution de mortalité se manifeste prrincipalement entrre 4 et 7
ans après le dépistage. Il cconvient de la me
ettre en perspectiive avec
e de vie de la pop
pulation-cible. L’es
spérance de vie moyenne
m
l’espérance
de ce grou
upe d’âge est de 16 ans à 70 ans
s et de 13 ans à 74 ans
(données belges
b
de 2009).
Les données probantes
p
issues de ces essais contrôlés
c
random
misés ne
peuvent donner une réponse complète à notre qu
uestion de base. En
E effet,
andomisé, l’étude
e suédoise dite de
es “Two County”, a inclus
un seul essai ra
des femmes âgées
â
de 70 à 7
74 ans et le nombre de septuag
génaires
participant à ce
et essai était trop ffaible (10.000 pou
ur les deux groupes) pour
pouvoir mettre en évidence un effet statistiqu
uement significatiff sur la
ait entachée de biiais méthodologiques.
mortalité. De plus cette étude éta
11
4
4.1.2.
Amélioration de la qualité
é de vie des patiientes
Le dépistage ayant pour objectif de
L
d mettre en évid
dence des tumeurs de
p
petite
taille, un de
es avantages atte
endus est de perm
mettre des traitem
ments
m
moins
agressifs. Ni
N les données iss
sues de essais co
ontrôlés randomisés, ni
le
es données factuelles recueillies en
e Belgique, ne pe
ermettent de conffirmer
c
cette
attente.
L essais contrôlés randomisés n’ont
Les
n
quantifié ni le taux de récidiv
ves ni
l’évolution vers le
es stades métas
statiques de la maladie. Il est donc
mpossible d’infirm
mer ou de conffirmer l’hypothèse
e d’une réductio
on de
im
m
morbidité
sur cette
e base. Par contrre, la perte de qu
ualité de vie impu
utable
a métastases es
aux
st inclue dans le modèle
m
décrit ci-dessous.
L
Les
données be
elges dont nous disposons acctuellement ne nous
p
permettent
pas de
e valider cette assertion. Les donn
nées les plus récentes
(rapport KCE 150)) font état de 58%
% de chirurgie con
nservatrice versus
s 38%
d mastectomies totales dans les stades les moinss avancés (Stades I et
de
III). Près de 90% des
d bénéficiaires de la chirurgie cconservatrice reço
oivent
é
également
un traittement par radiothérapie, 38% d’entre elles reçoive
ent un
trraitement de ch
himiothérapie né
éo-adjuvante et 41% un traite
ement
h
hormonal.
4
4.2.
Estimation
n des inconvén
nients du dépisstage
4
4.2.1.
Diminutio
on de la qualité de
d vie des particcipantes
Le dépistage prov
L
voque une diminuttion de la qualité d
de vie d’une partie
e des
p
personnes
dépisté
ées. Ceci s'expliqu
ue par une série d
de facteurs:
1. Les résultats faussement pos
sitifs du dépistage
e sont perçus pa
ar les
mme de vrais pos
sitifs, aussi longtemps que les examens
patientes com
complémentaires n’ont pas pe
ermis de les infirm
mer. Ils provoque
ent de
ar rapport au canc
cer du sein et auxx procédures inva
asives
l'inquiétude pa
telles que les ponctions mamm
maires.
2 Les diagnostic
2.
cs excédentaires et les traitementss qui les suivent (over(
diagnosis and
d over-treatment,, pour plus de d
détails, voir le ra
apport
scientifique) conduisent
c
à des inquiétudes grave
es et à des traitem
ments
lourds dont de
es amputations mammaires
m
qui n’o
ont pas d’influenc
ce sur
la survie de la
a personne.
12
3.
S
Screening
Breast Cancer
C
L’avance au
a diagnostic peu
ut entrainer une perte
p
de plusieurs années
de vie en bonne
b
santé. Le d
dépistage a pour objectif de diagn
nostiquer
le cancer plus
p
précocementt que ne le ferait un
u diagnostic clin
nique. La
patiente de
evient de ce fait m
malade du cancerr plus tôt dans le décours
de sa vie. Toutefois, si cette patiente
e décède d’une
e cause
elui-ci n’ait eu le
e temps
indépendante de son canccer avant que ce
alade du cancer” quelques années
s trop tôt
d’évoluer, elle aura été “ma
u diagnostic et au
a traitement n’a
aient pu
sans que cette avance au
s espérance de
e vie10.
influencer son
4.3. Approche par modélissation
Les revues de littérature précitée
es ne nous ayantt pas permis de quantifier
q
b
et des risques, nous av
vons construit un modèle
le poids des bénéfices
spécifique dans ce but. La construction de ce modèle a nécessité de
e des femmes pe
endant le
rechercher les études relatives à la qualité de vie
adie.
dépistage et à la qualité de vie des patientes au cours de leur mala
4.3.1. Mesure
res de la qualité de la vie
Différents instruments sont disp
ponibles pour me
esurer la qualité de vie.
ments sont spécifiquement adaptés à la maladie, comme
Certains instrum
par exemple, le
l questionnaire relatif à la qualité de vie des patientes
p
atteintes d'un cancer
c
du sein de l'European Organ
nization for Resea
arch and
Treatment of Cancer
C
(EORTC).. Ces outils évalu
uent l'image du corps,
c
le
fonctionnementt physiologique, la peur de la récidive… Toutefois, il n'est
pas possible de prendre en compte ces do
onnées de santé
é multis dans un modè
èle. Elles doiven
nt être converties
s en un
dimensionnelles
indice global de
d qualité de vie
e, à savoir, le Quality-Adjusted
Q
L
Life-Year
(QALY). Les QALYs sont le nom
mbre d’années de
e vie ajustées à la
a qualité
de vie.
d KCE, considèrrent que
Les recommandations pharmacco-économiques du
ensions)
le questionnaire appelé EQ-5D (European Quality of Life-5 Dime
eilleurs instrumen
nts disponibles pour
p
évaluer les QALYs.
est un des me
Avec cet instrument, la qualité d
de la vie liée à l'état de santé est mesurée
m
obilité, l’autonomiie de la
en prenant en compte cinq dimensions: la mo
antes, la doule
eur/la gêne, l’anxiété/la
personne, les activités coura
our chacune de cces dimensions, plusieurs répons
ses sont
dépression. Po
possibles. Celles-ci reflètent le niveau de sévérité du problème
e (aucun
KCE Reportt 176
problème, quelqu
p
ues problèmes, des problèmess modérés, ou des
p
problèmes
graves) Ce questionnairre est soumis à la population conce
ernée,
s en ce qui conc
soit
cerne le dépistage, une population
n de femmes indemnes
d cancer du sein
du
n et en ce qui co
oncerne la malad
die, une populatio
on de
p
personnes
atteintes de ce cancerr. La revue de lla littérature a permis
d
d’identifier
trois éttudes qui correspondaient à nos ccritères d’inclusion
n. Sur
b
base
de ces étude
es, les variations de la qualité de vvie des septuagén
naires
s
sont
estimées com
mme suit:
1. La perte de qualité de vie co
onsécutive à un résultat de dépistage
p
est estimée
e à 16% pendant la période néces
ssaire
faussement positif
pour infirmerr ce faux positif.. En Belgique, ccette période durre en
moyenne 45
5 jours (minimum
m 36, maximum 54 jours) selon
n les
données AIM (Agence Intermu
utualiste)
2 Pour les patie
2.
entes cancéreuses et pendant la première année qu
ui suit
le diagnostic (quel
(
que soit le traitement), la pertte de qualité de vie
v est
estimée à 16% pour les stade
es I, II, III et à 18
8% pour les stade
es IV.
a
suivantes, la perte de qualitté de vie est estim
mée à
Pendant les années
6% pour les stades I,II,III. Ce
ette perte demeu
ure stationnaire (18%)
(
es IV.
pour les stade
P
Plusieurs
limitatio
ons de cette app
proche nous oblig
gent à interpréter ces
c
chiffres
avec préc
caution. Il s’agit de
d résultats provvenant de pays angloa
s
saxons.
Le questio
onnaire utilisé, à savoir, l’EQ-5D m
mesure les dimen
nsions
s
sanitaires
générales et non les dim
mensions spécifiqu
ues au cancer du sein.
L mesures conc
Les
cernant les patien
ntes ne prennent q
ent en
que sommaireme
c
compte
l’impact à court terme du
d diagnostic ett de la chirurgie
e. Ce
q
questionnaire
aya
ant été utilisé lorrs des consultatio
ons ambulatoires
s; ses
ré
ésultats ne reflè
ètent pas la qua
alité de vie des patientes grave
ement
m
malades
ne pouva
ant plus se déplac
cer. Les particularités de l’étude uttilisée
p
pourraient
expliquer le faible chang
gement de qualité
é de vie constaté entre
le
es patientes ayan
nt un cancer du sein
s
et la populattion générale ou entre
le
es patientes ayan
nt développé des métastases
m
et celles qui n’en ont pa
as.
4
4.3.2.
Descriptio
on du modèle
Le modèle compa
L
are deux cohorte
es théoriques. Ce
es deux cohortes
s sont
c
constituées
de 100.000 femmes do
ont l’évolution est suivie jusqu’à la mort.
L schéma ci-dess
Le
sous représente cette
c
évolution:
KCE Report 176
6
S
Screening
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C
(1) cancer invasif diagnostiqué lors du dép
pistage Femmes invitées Cohortte A (2) cancer d'intervalle (3
3) cancer invasif diagnostiqué dans le grroupe des non‐
paarticipantes 13
I
II
III
IV
I
II
III
IV
(5) Décès (toutes causes co
onfondues)
I
II
III
IV
(4)) Cancer canalaire in situ
Cohortee B
Femmes non invitées (6
6) cancer invasif diagnostiqué dans le grroupe des non‐
in
nvitées (7
7) Cancer canalaire in
n situ diagnostiqué
d
dans le groupe des n
non‐invitées I
II
III
IV
(8) Décès (toutes causes co
onfondues)
14
S
Screening
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C
La cohorte A illustre l’hypothèse
e d’une prolongatio
on du dépistage organisé
o
s. Elle est constiituée des femme
es invitées au dé
épistage.
jusqu’à 74 ans
Parmi celles-ci, certaines participent au dépistag
ge (invitées/partic
cipantes)
c
survenantt dans la
et d’autres non (invitées/non-parrticipantes). Les cancers
épertoriés. Il s’ag
git soit de cance
ers diagnostiqués lors du
cohorte sont ré
dépistage (1), soit de cancers d
diagnostiqués dans l’intervalle enttre deux
épistage (2), soit de cancer diagn
nostiqués dans le
e groupe
sessions de dé
des invitées/no
on-participantes ((3). Enfin, les ca
ancers canalaires
s in situ
peuvent surven
nir dans le group
pe des invitées/p
participantes tout comme
dans le groupe
e des invitées/non
n-participantes (4)). La très grande majorité
des femmes co
onstituant cette co
ohorte décèdera d’une autre affec
ction que
le cancer du se
ein (5).
La cohorte B (c
cohorte de contrô
ôle) correspond à la situation actue
elle. Les
membres de ce
ette cohorte ne ssont pas invitées au dépistage. Certaines
C
femmes serontt atteintes d’un cancer invasif (6
6), d’autres d’un
n cancer
canalaire in situ
u (7). La très gran
nde majorité des femmes constitua
ant cette
cohorte décède
era d’une autre afffection que le can
ncer du sein (8).
Le cancer du sein
s
évolue en qu
uatre stades (I, II, III, IV). Le stade
e I est le
stade le moins avancé. La survie
e est d’autant moins bonne et le tra
aitement
ourd et plus invassif que le stade est avancé au moment du
d’autant plus lo
diagnostic.
4.3.3. Hypoth
hèses de base
L’hypothèse de
e base est la suiivante: parmi les cancers détectés par le
dépistage, la prroportion de stade
es peu avancés (II et II) est plus importante
que parmi les cancers diagnosstiqués sur base
e de la clinique. Tout le
épistage provientt des différences
s dans la répartittion des
bénéfice du dé
stades (stage-s
shift) consécutive au dépistage.
L’autre hypothè
èse retenue est que la survie et
e la qualité de vie des
femmes dépendent uniquementt du stade de la tumeur et de l’âg
ge de la
ment du diagnosttic, que celui-ci soit
s consécutif ou non au
femme au mom
dépistage.
Les cohortes sont
s
suivies d’ann
née en année et évoluent en fonction de
paramètres de
e transition tels lle nombre de fe
emmes atteintes chaque
année (incidenc
ce) et le taux de ssurvie en fonction du stade du canc
cer.
KCE Reportt 176
4
4.3.4.
Alimentattion du modèle
Pour réaliser cet exercice,
P
e
nous av
vons autant que ffaire se peut, alim
menté
n
notre
modèle avec des données belges.
b
Ces param
mètres sont décriits en
d
détails
dans le cha
apitre 3.3. du rapp
port.
L
L’espérance
de vie de la population étudiée provien
nt des tables de survie
s
d la population féminine
de
f
belge du
u même âge. L’in
ncidence du canc
cer en
fo
onction de l’âge et
e des stades de la
l maladie provien
nt du registre belg
ge du
c
cancer
(Communa
auté flamande). Les données relatiives au dépistage
e sont
is
ssues des progra
amme actuels (ffemmes de 50-69
9 ans en Wallon
nie, à
B
Bruxelles
et en Co
ommunauté Flama
ande).
U mesure de qualité de vie a été
Une
é appliquée à cha
aque compartime
ent du
m
modèle.
Le modèlle contient un cas
s de base (base ccase) qui correspo
ond à
la
a situation la plus vraisemblable.
“
“Par
essence, tous
s les modèles son
nt faux mais certains sont utiles”a
4
4.3.5.
Analyse de
d sensibilité
Dans notre modè
D
èle, nous avons émis un certain nombre d’hypoth
hèses
s
simplificatrices,
en
n raison des données dont nouss disposions et de la
n
nécessité
d’éviter l’utilisation d’un modèle
m
trop comp
plexe. Ce choix co
onduit
à une incertitude
e liée à la struc
cture du modèle
e, au bon choix
x des
p
paramètres
et de
e la source des informations. P
Pour faire face à ces
d
différents
types d’iincertitude, nous avons
a
réalisé une
e analyse de sens
sibilité
a
approfondie
utilisa
ant différents scé
énarios. Ces diffférents scénarios sont
d
décrits
en détails dans
d
la table 3.2 du
d rapport scientiffique.
a
citation attribuée au statisticien George
G
Box.
KCE Report 176
6
S
Screening
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C
5. RÉSULTATS
Le scénario de
e base montre que la prolongation du dépistage jus
squ’à 74
ans permettraitt d’éviter 1,3 décè
ès pour 1000 femmes participantes
s, ce qui
représente une
e réduction de 2
21% des décès. Globalement, le nombre
d’années de vie
e sauvées est estiimé à 13,1 et le gain en QALY à 3,9.
L’analyse de se
ensibilité du modè
èle comprend un scénario
s
pessimis
ste et un
scénario optimiste .
Le scenario pe
essimiste fait l’hyypothèse d’un ex
xcédent de diagnostic de
20%, d’un taux de faux positifs d
de 10%, entrainan
nt une perte de qu
ualité de
durant pendant 54
4 jours (temps né
écessaire pour infiirmer les
vie de 0,19 perd
résultats). La distribution des cancers dépisté
és par stades observée
o
ans le cadre du d
dépistage organisé en Flandre (50--69 ans)
actuellement da
a été appliqué
ée au groupe d
dépisté. Ce scén
nario pessimiste permet
d’estimer un ga
ain de 8,7 année
es de vie mais une perte de 3,1 QALYs
pour 1000 fem
mmes participantt au dépistage. Ceci signifie qu
ue dans
certaines circon
nstances, au dem
meurant tout à fa
ait réalistes, le dé
épistage
peut aboutir à une
u perte en terme
e de qualité de vie
e.
Le scenario optimiste fait l’hypotthèse d’un excédent de diagnostic
c de 3%,
%, entrainant une perte
p
de qualité de
d vie de
d’un taux de faux positifs de 2%
pplique au groupe
e dépisté
0,13 perdurant pendant 36 jourss. Ce scénario ap
ment dans le ca
adre du
la distribution par stades obsservée actuellem
anisé aux Pays-B
Bas (70-74 ans)). Ce scénario optimiste
o
dépistage orga
permet d’estime
er un gain de 17,0 années de vie et un gain de 16,,2 QALY
pour 1000 fem
mmes participant au dépistage. Ceci signifie qu’’il serait
nécessaire d’inv
viter 62 femmes à participer au dé
épistage pendant cinq
c
ans
pour gagner un QALY.
15
6 DISCUS
6.
SSION
Les résultats du modèle
L
m
décrit ci-de
essus indiquent que en ce qui conc
cerne
la
a situation de base, le gain en an
nnées de vie est de 13 ans pour 1000
fe
emmes dépistées
s. Ce résultat res
ste fiable tout au
u long de l’analys
se de
s
sensibilité.
A l’inv
verse, les QALYs
s varient substan
ntiellement en fon
nction
d
des
hypothèses choisies,
c
allant d’un
d
gain relative
ement faible à, selon
c
certaines
hypothès
ses plausibles, un
ne perte en qualité
é de vie.
6
6.1.
Ajouter de
es années à la vie ?
L’augmentation de
L
e l’espérance de vie de la femme est un des argum
ments
u
utilisés
pour justifier de poursuivre le dépistage du ccancer du sein ch
hez la
fe
emme âgée de plus de 69 ans. Cet argument présuppose qu
ue la
p
population
des septuagénaires
s
a les mêmes ca
aractéristiques qu
ue la
p
population
des sexagénaires. Il n’en
n
est rien en
n ce qui concern
ne la
frréquence et les ca
auses de décès.
L nombre de dé
Le
écès observé dan
ns la tranche d’âg
ge des 70-79 an
ns est
d
deux
fois et demi plus élevé que ce
elui de la tranche
e d’âge des 60-69
9 ans.
E fait, la population féminine belge
En
e perd 4% de sess effectifs entre 50
0 à 59
a
ans,
8% entre 60 à 69 ans et 20%
% entre 70 à 79 ans (Belgian life table
2
2009).
L causes de dé
Les
écès varient égallement. En Belgiq
que, la proportion
n des
d
décès
dus au can
ncer du sein pass
se de 13% entre 60 et 64 ans à 6%
6 de
to
ous les décès en
ntre 70 et 75 ans. A cet âge, la mo
ortalité par cance
er tout
c
comme
la mortalité cardiovascula
aire sont pratique
ement équivalentes et
re
esponsables chac
cune d’un peu plu
us d’un tiers des décès. Parmi tou
us les
d
décès,
la part de décès
d
consécutifs
s au cancer du se
ein diminue donc avec
l’âge (KCE report 11).
16
S
Screening
Breast Cancer
C
KCE Reportt 176
6.2. Ajouter de la (qualité d
de) vie aux ann
nées ?
7 CONCLU
7.
USIONS
6.2.1. Traitem
ments moins agrressifs?
7
7.1.
Faut-il pro
olonger le dépis
stage jusqu’à l’âge de 74 ans
s?
Outre le gain en
n années de vie, le principal avanta
age attendu du dé
épistage
est de permettre des traitements moins agre
essifs. Toutefois,, ni les
s de essais contrô
ôlés randomisés, ni les données fa
actuelles
données issues
recueillies en Belgique,
B
ne perme
ettent de confirme
er cette attente.
6.2.2. Faux positifs
p
Dans notre mod
dèle, les diagnosttics ”faussement positifs” représentent une
source importante de perte de q
r
qualité de vie. Un taux élevé de résultats
ositifs (pouvant a
aller jusqu’à 10%
%) conjugué à un
u délai
faussement po
d’attente relativ
vement élevé (45
5 jours en moye
enne) pour les examens
e
complémentaire
es peut amener à un résultat total du dépistage né
égatif en
termes de QA
ALY. Si on parvient à garder ce
e taux dans les normes
européennes (3
3,5%) comme c’e
est le cas dans une région du pays
p
(en
Flandre), le gain en QALY est de
e 3 pour 1000 fem
mmes.
6.2.3. Excès de diagnostics e
et de traitements
s
Le risque de diagnostic excéden
ntaire est le risque
e majeur de ce dé
épistage
agénaires. Si nouss appliquons un ta
aux de surdiagnos
stic de 3
pour les septua
%, on peut s’atttendre à ce que d
dans chaque cohorte de 100.000 femmes,
f
108 femmes su
upplémentaires auront un diagnos
stic de cancer et subiront
très vraisembla
ablement un traitement. Si nous appliquons un taux de
surdiagnostic de 10 %, ce nombrre monte à 367.
D’autre part, toutes
t
les femme
es dont le canc
cer est diagnostiq
qué par
screening devie
ennent malades d
du cancer deux ou
o trois ans plus tôt
t qu’en
cas de diagnos
stic clinique. Cecci a un impact négatif
n
sur la qua
alité des
années de vie qui
q leur restent.
La conclusion de cette étude est que la réponse à ccette question estt non.
L
C
Cette
affirmation est basée, d’une
e part, sur les ré
ésultats du modè
èle et
d
d’autre
part sur le
e contexte spécifiq
que de cette question. Les résulta
ats du
m
modèle
démontre
ent un gain de 13
1 années de vie pour 1000 fem
mmes
d
dépistées.
Toutefo
ois, certaines hyp
pothèses qui sontt loin d’être irréallistes,
in
ndiquent que le résultat net du prolongement d
du dépistage po
ourrait
ré
ésulter en une pe
erte globale en qu
ualité de vie. Ces résultats ne sont donc
p décisifs en ta
pas
ant que tels et do
oivent être interprrétés dans le con
ntexte
p
particulier
d’un dé
épistage organisé
é. Le dépistage o
organisé s’adresse par
d
définition
à un individu qui n’ex
xprime ni plainte
e ni demande. Cette
s
spécificité
implique d’être d’autant plus vigilant auxx principes éthiqu
ues11.
L trois principes
Les
s éthiques de bas
se applicables nottamment au dépistage
s
sont:
les principes
s de bienfaisance
e ou de non malfa
aisance, le princip
pe de
ju
ustice ou d’équité et le principe d’autonomie12.
L principes de bienfaisance
Les
b
ou de
d non malfaisancce sont définis co
omme
s
suit:
“Ne pas faire
e de mal (primum
m non nocere) esst le premier. Il do
oit se
d
doubler
d’un devo
oir de bienfaisanc
ce qui va de pairr avec une attitud
de de
b
bienveillance”.
Le principe de justic
ce ou d’équité estt: “cette préoccup
pation
q fait intervenir la
qui
l dimension colle
ective des problèm
mes de santé, da
ans le
s
sens
d’une préfére
ence pour les plus
s faibles, les plus démunis”12.
L dépistage estt organisé dans le but d’améliorrer le bien-être de
Le
d la
p
population
en évittant notamment des
d décès préma
aturés. Cependan
nt, les
ré
ésultats obtenus par le modèle ne
n permettent pa
as d’exclure que dans
c
certaines
situation
ns, le dépistage puisse
p
affecter négativement la qualité
d vie dans la tran
de
nche d’âge étudié
ée. Dans ces cond
ditions, il y a risqu
ue de
v
violation
du princip
pe de base ”primu
um non nocere”(ne
e pas faire de mal).
KCE Report 176
6
S
Screening
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C
D’autre part, le
e dépistage est nettement moins efficace
e
pour les femmes
dont l’espéranc
ce de vie est la plus basse. Cette différence d’e
efficacité
existe certes dans
d
les autres tranches d’âge mais elle y es
st moins
prononcée. Le respect du princcipe de justice ou
u d’équité se révè
èle donc
n supplémentaire de répondre par la négative à la question
q
être une raison
posée.
7.2. Que rép
pondre à la perrsonne qui dem
mande un dépis
stage?
Le contexte de cette question d
diverge de celui de la question pré
écédente
s: l’individu est de
emandeur et le problème
p
doit être
e évalué
en deux points
sur un plan individuel. Le princip
pe d’autonomie s’’applique particulièrement
pe est défini comme suit: ”le respe
ect de la
bien à cette situation. Ce princip
l principe de base, le respect de l’autonomie de
d cette
personne est le
personne en découle ; Il s’agit de reconnaître la
a capacité de l’in
ndividu à
autodétermination
n et libre choix) et
e à régir
faire des choix pour lui-même (a
our que la personne puisse faire un libre
sa conduite (autogestion)”12. Po
mée des
choix, il imporrte qu’elle soit cclairement et corrrectement inform
avantages et des inconvénie
ents du dépista
age dans sa situation
s
e droit d’être inforrmé (Article 7) et le droit au conse
entement
personnelle. Le
éclairé sont dé
écrits dans la loi belge relative au
ux droits des patients. Le
consentement éclairé de la patiente ne peut être
e obtenu uniquem
ment sur
ure d’un documen
nt d’information. Il s’agit d’un processus qui
base de la lectu
devrait idéalement inclure un éch
hange d’idées ave
ec le praticien.
Il convient éga
alement que le m
médecin développe pour sa patie
ente qui
demande le dé
épistage, une stra
atégie qui en minimise les inconvénients13.
Ainsi, une attitu
ude articulée en tro
e:
ois étapes peut êttre recommandée
•
Information
n spécifique à la trranche d’âge
•
Prise de décision
d
en foncction de l’appréc
ciation personnelle de la
patiente14.
•
n de la personne qui le souhaite ve
ers un dépistage dont les
Orientation
modalités minimisent
m
les incconvénients.
17
Les critères défin
L
nis dans le cadrre du programme
e européen prév
voient
n
notamment
la su
urveillance de la
a qualité techniq
que des équipem
ments
u
utilisés,
la double lecture des mammographies et l’o
optimisation du tau
ux de
ra
appel1. En Belgique, les unités de mammographie a
agréées répondan
nt aux
c
critères
définis dans le cadre du prrogramme europé
éen, il est donc logique
d
d’orienter
les femm
mes qui demande
ent explicitement un dépistage verrs ces
s
structures.
7
7.3.
Message clé
Le dépistage estt organisé dans le but d’améliorrer le bien-être de
L
d la
p
population
en évitant notamment des décès prématu
urés. Il est certain
n que
p
prolonger
le dépistage jusqu’à l’âge
e de 74 ans devra
ait permettre de ga
agner
q
quelques
années de vie. Toutefo
ois, l’influence de
e cette mesure sur
s la
q
qualité
de vie est
e
nettement pllus aléatoire. Se
elon des hypoth
hèses
ra
aisonnables, cettte intervention po
ourrait même ab
boutir à une pertte en
te
erme de qualité de
d vie. Dans ces conditions, il se p
pourrait que la balance
b
bénéfices-risques
d’une perte globa
ale de
de ce dépistage penche du côté d
b
bien-être
de la pop
pulation.
18
S
Screening
Breast Cancer
C
KCE Reportt 176
8. RÉFÉR
RENCES
1.
2.
3.
4.
5.
6.
7.
Perry N,
N Broeders M, de
e Wolf C, Tornberg
g S, Holland R, vo
on Karsa
L. Euro
opean guideliness for quality assu
urance in breastt cancer
screeniing and diagnosiss. Fourth edition---summary docume
ent. Ann
Oncol. 2008;19(4):614-2
22.
Schwarrtz LM, Woloshin
n S. News media
a coverage of sc
creening
mammo
ography for women in their 40s and
a
tamoxifen for primary
preventtion of breast cancer. JAMA. 2002;287(23):3136-42..
Schwarrtz LM, Woloshin S, Fowler FJ, Jr.., Welch HG. Enthusiasm
for cancer screening in the United States
s. JAMA. 2004;29
91(1):718.
man E, Woloshin S, Schwartz LM
M, Byram SJ, We
elch HG,
Silverm
Fischho
off B. Women's vviews on breast cancer
c
risk and sc
creening
mammo
ography: a qualittative interview sttudy. Med Decis Making.
2001;21(3):231-40.
Schwarrtz LM, Woloshin S, Sox HC, Fisc
chhoff B, Welch HG. US
women
n's attitudes to fa
alse positive ma
ammography resu
ults and
detectio
on of ductal carcinoma in situ: cros
ss sectional surve
ey. BMJ.
2000;32
20(7250):1635-40
0.
Belgian
n Cancer Registrry, editor. Cance
er incidence in Belgium,
B
2004-2005. Brussels; 20
008.
Paulus D, Mambourg F, Bonneux L. [Brea
ast cancer screening].
C
Practice (G
GCP). Brussels: Belgian
B
Health Care
Good Clinical
Knowle
edge Centre (KCE
E); 2005 02/05/200
05. KCE Reports 11
Availab
ble from:
http://kc
ce.fgov.be/index_
_en.aspx?SGREF=5221&CREF=93
348
8
8.
9
9.
10.
11.
12.
13.
14.
Mandelbla
att JS, Cronin KA
A, Bailey S, Berrry DA, de Koning
g HJ,
Draisma G, et al. Effects of mammogra
aphy screening under
u
dules: model esstimates of pottential
different screening sched
m appears in Ann
n Intern Med. 2010
0 Jan
benefits and harms.[Erratum
0):738-47.
19;152(2)::136]. Ann Intern Med. 2009;151(10
Woloshin S, Schwartz LM, Byram SJ, Sox H
HC, Fischhoff B, Welch
W
men's understand
ding of the mam
mmography screening
HG. Wom
debate. Arrch Intern Med. 20
000;160(10):1434
4-40.
Mandelbla
att JS, Silliman R. Hanging in the balance: making
decisions about the benefits
s and harms of brreast cancer screening
e oldest old witho
out a safety net o
of scientific eviden
nce. J
among the
Clin Oncol. 2009;27(4):487--90.
Doumont D, Verstraeten K. Enjeux éth
hiques du dépistage
unauté Française. 2012(7):3-7.
organisé. Santé en Commu
D
les ca
ancers, mais à quelle condition
n In:
Gallois. Dépister
UNAFORM
MEC, editor. Médecine. Paris; 2005
5. p. 72-7.
USPSTF. Screening for Brreast Cancer: U.S
S. Preventive Serrvices
dation Statementt Annals of Intternal
Task Forrce Recommend
Medicine 2011(151):716-26
2
6.
Woloshin S, Schwartz LM. The bene
efits and harm
ms of
AMA.
mammogrraphy screening: understanding tthe trade-offs. JA
2010;303((2):164-5.
KCE Report 176
6
„ SCIENTIFIC REPORT
T
S
Screening
Breast Cancer
C
19
1 INTROD
1.
DUCTION
1
1.1.
Context of
o this report
This report is a partial update of the clinical practicce guideline (CPG
T
G) on
b
breast
cancer screening published
d in 20051. Therefore, the KCE ex
xperts
m
made
a list of clinical
c
questions
s related to brea
ast cancer scree
ening.
R
Representatives
o stakeholders’ orrganizations were
of
e then invited to re
eview
th
he choice and the
e wording of the questions, to highliight the main prob
blems
re
elated to each question and to score the relevance of cllinical
q
questions(see
KC
CE report 172)2. Selected questio
ons were then divided
o
over
three KCE re
eports. A first KCE
E report published
d in 2010 is focuse
ed on
b
breast
cancer scre
eening with mam
mmography for wo
omen in the age group
g
o 40-49 years (KC
of
CE report 129)3. The second is focused on identific
cation
o women at risk fo
of
or breast cancer and
a technical metthods for breast ca
ancer
s
screening
(KCE re
eport 172)2.
1
1.2.
Scope of this report
This report focuse
T
es on the extensio
on of organized brreast cancer screening
w
with
mammography to older wom
men. Eligible pop
pulation is define
ed as
w
women
between 70-74
7
years of age
e with average risk of breast cancer.
1
1.3.
Breast ca
ancer screening
g in Belgium
The Belgian fed
T
deral and regional governmentss signed a pro
otocol
a
agreement
in 200
01 for an organized screening programme for wo
omen
a
aged
50-69 years
s, to be organiz
zed by the regional governments
s with
a
appropriate
financ
cial resources sup
pplied by the fede
eral government. Since
S
2
2001,
Flanders, th
he Walloon region
n and the Brusse
els capital region have
e
each
introduced an
a organized scre
eening programm
me within their sp
pecific
c
context
of alread
dy existing practtices. Indeed, op
pportunistic screening
re
emains quite freq
quent in the Wallo
oon and Brussels region among wo
omen
in
n the age-group 50-69,
5
but also among
a
younger (4
40-49 years of ag
ge) or
o
older
women (>7
70 years). In Flanders, screening mammographies
s are
d
dominant
in the ag
ge-group 50-69. In the age-group 7
70-79 overall cove
erage
d
drops,
mainly beca
ause organized sc
creening stops at age 69. The cove
erage
b means of diagn
by
nostic mammogra
aphy decreases also with 3%, indic
cating
th
hat substitution of screening mamm
mography by opp
portunistic screeniing at
20
S
Screening
Breast Cancer
C
the age of 70 is not frequent in Flanders. At this age, total coverage
c
ortunistic
(including both diagnostic or folllow up mammogrraphies and oppo
mains at 18% in F
Flanders, 33% in Brussels and 30%
% in the
screening) rem
Walloon region (KCE report 172))2.
1.4. Clinical questions
This specific report addresses th
he following questiions:
1. What are clinical
c
benefits off an extension off breast cancer orrganized
screening in
i women betwee
en 70 and 74 years
s?
1.1. What is the effect of an
n extension (70-74
4 years) of breas
st cancer
er related mortality
y?
organized screening on the breast cance
ong is the delay b
between the scree
ening and the associated
1.2. How lo
breastt cancer related m
mortality reduction?
?
1.3. What is the effect of an
n extension (70-74
4 years) of breas
st cancer
organized screening on the overal mortallity?
n extension (70-74
4 years) of breas
st cancer
1.4. What is the effect of an
organized screening on morbidity?
ension of breast cancer
2. What are the specific harms of an exte
s
in wom
men between 70 and 74 years?H
Harms in
organized screening
terms of false positive o
or false negative re
esults?
2.2. Harms
s in terms of additional diagnostic te
ests?
2.3. Harms
s in terms of over--diagnosis?
2.4. Harms
s in terms of overttreatment?
3. What attitu
ude should be re
ecommended for women in case
e of self
referral?
KCE Reportt 176
1
1.5.
Scientific approach
For each clinical question, a sys
F
stematic search of the literature was
p
performed
and dis
scussed with the support of extern
nal experts chose
en for
th
heir scientific co
ompetency in se
everal fields: gyynaecology, radio
ology,
e
epidemiology,
or health economic
cs. For question
n 3, we searche
ed for
m
models.
To quan
ntify what the im
mplications of ourr findings are on
n the
B
Belgian
situation we applied da
ata from the Intermutualistic Ag
gency
(IMA/AIM), cancerr registry and datta from the literature on the Belgia
an life
ables and constru
ucted a simple tim
me dependent Markov chain with annual
ta
c
cycles.
T methodology used and the resu
The
ults are described
d in each chapter.
KCE Report 176
6
S
Screening
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C
2. LITER
RATURE RE
EVIEWS
2.1. Review
w of clinical stud
dies
2.1.1. Metho
odology
2.1.1.1. Sou
urces
A broad searc
ch of the electronic databases OVID
O
Medline, EM
MBASE,
CDSR and DAR
RE was conducted
d in April 2011. Se
earch was conduc
cted first
for systematic reviews
r
(SR) and meta-analysis (M
M-A).
2.1.1.2.
Sea
arch terms
For searching on
o Medline database, the following
g MeSH terms we
ere used
in combination with usual langua
age: Breast neoplasms (MESH) an
nd mass
e
detection) ((MESH) and mam
mmography (MES
SH). For
screening (or early
EMBASE, the following Emtree terms were used:
u
'cancer scrreening',
phy'. These MESH
H and Emtree term
ms were
'breast cancer' and 'mammograp
entify systematic reviews
combined with a standard searcch strategy to ide
nalysis (M-A).
(SR) or meta-an
2.1.1.3.
In- and exclusion crriteria
Databases werre searched for S
SR and M-A in English,
E
French, Dutch
D
or
German. This report
r
is a update
e of previous KCE
E report1 (search made in
2004), thus we
w used a date restriction (2004
4-2011) and a la
anguage
restriction (English, Dutch, Frencch and German). Inclusion criteria used for
d on title, abstra
act or full text were:
w
population (women
selection based
without breastt cancer and w
without particula
ar breast cance
er risk),
intervention (m
mammography), o
outcome (mortality, morbidity, additional
diagnosis tests, over diagnosis and over treatme
ent), design (SR or
o metaCT), key question (screening), age
e of population (>
>70 and
analysis or RC
<75 years), and original publica
ation. Relevant pu
ublications were selected
b 2 reviewers (FM
M, JR).
independently by
2
2.1.1.4.
21
Additio
onal evidence
We identified two SR4, 5 as the more
W
m
extensive so
ource for the rese
earch
q
question
2. Therrefore the evide
ence-identified through those SR
R-was
u
updated
by search
hing Medline and the Cochrane Database of Systematic
R
Reviews
from the search date of the
t
two SR’s on (search date Nov
v-Dec
2
2008).
Additional hand
h
searching of
o reference lists w
was also undertak
ken to
e
ensure
that no potentially relevant studies were missed. We also sca
anned
re
eference lists off SR and of ou
ur previous repo
ort on breast ca
ancer
3
s
screening
.
T
The
identified studies were selecte
ed based on title
e and abstract. For
F all
e
eligible
studies, the full-text was
s retrieved. In ccase no full-text was
a
available,
the stud
dy was not taken in
nto account.
T
The
description and results of the literature searche
es and flow of sttudies
s
search
are in Appe
endix 1.1.
2
2.1.1.5.
Quality
ty appraisal
The methodologic
T
cal quality of systtematic reviews a
and associated riisk of
b
bias
were rated using the check
klists of the Dutch Cochrane Centre
C
(w
www.cochrane.nl). The assessmen
nt of the risk of b
bias in the include
ed SR
w conducted by
was
y a team of two rev
viewers (FM, JR)..
T methodologic
The
cal quality of selec
cted additional evvidence was also rated
u
using
the adeq
quate checklists of the Dutch Cochrane Centre
C
(w
www.cochrane.nl).
T results of the quality appraisal are
The
a in Appendix 1.5.
2
2.1.1.6.
Identiffied systematic reviews
r
In
n the systematic search for literature reviews, 53 citations on the topic
w
were
identified in
n database searrches. The majo
ority of citations were
e
excluded
on the basis
b
of title and abstract; 10 citattions were retriev
ved in
fu
ull and reviewed in more detail. On
O the basis of tthe full text, 5 rev
views
w
were
included4-8.
T
The
reviews writte
en by Götzsche and Nelson4, 5 a
are mainly focuse
ed on
m
mortality
as outco
ome, those from Biesheuvel and JJorgensen6, 7 on overd
diagnosis
and the review of Virnig8 on ductal carcinoma in situ (DCIS).
22
S
Screening
Breast Cancer
C
KCE Reportt 176
As a first step,, a quality appraisal of all the rev
views was carried out to
4 5
determine theirr suitability for incclusion. Götzsche
e and Nelson SR4,
were
5
judged to be off high quality with a low risk of bias
s. Nelson review was an
update of one
e other review performed by Humphrey
H
for th
he U.S.
Preventive Tas
sk Force9. Humph
hrey review was also
a
judged to be
e of high
quality and used here as comple
ementary information source.
The review writtten by Biesheuve
el6 was judged to be
b of good quality
y (quality
appraisal of selected trials not ssufficiently describ
bed) and those written
w
by
s judged to be off high quality. The
e review written by
b Virnig
Jorgensen7 was
was also judged
d to be of high quality.
For DCIS, this upd
F
date was carried out in July 2011 identifying 7 citations.
A citations were excluded
All
e
on the basis
b
of title and abstract.
F overtreatmentt, this update was
For
s carried out in Ju
uly 2011 identifyin
ng 19
c
citations
on Medlin
ne and 7 citations
s on the Cochrane
e Library. The ma
ajority
o citations were excluded
of
e
on the basis
b
of title and abstract; 2 pape
ers on
o
overtreatment
werre retrieved in full and reviewed in more detail. On the
b
basis
of the full te
ext, we retrieved again
a
the SR writtten by Götzsche4 and
s
selected
one pub
blication presentiing data issued from the UK Breast
B
S
Screening
Program
mme11. The description and resultss of those update
es are
in
n Appendix 1.4.
2.1.1.7.
2
2.1.1.9.
Iden
ntified RCT
5
The evidence was
w updated using
g the key words reported in Nelson
n SR by
searching Med
dline and the Cocchrane Database
e of Systematic Reviews
R
from the search
h date of this SR on (search date Nov 2008). The literature
search for relev
vant RCTs carried out in Medline, EMBASE and CCRT
C
(in
April 2011) iden
ntified 432 citation
ns. The majority of
o citations were excluded
e
on the basis off title and abstractt; the other paperrs (n=8) were retrrieved in
full and review
wed in more deta
ail. On the basis of the full text, all eight
studies were ex
xcluded because of the study des
sign (not an RCT
T) shows
the flow of rand
domized controlled
d trials from selec
ction to in-or exclusion.
By hand searc
ching of referencce lists of Götzs
sche and Nelson4, 5, the
Swedish RCT’s
s were identified. Among those, the
e Two County tria
als is the
only RCT tha
at includes wom
men aged 70-74 years at the time of
randomization. Quality appraisall of this RCT was
s carried out to de
etermine
f inclusion. The Two County trials was judged to be
b of fair
their suitability for
quality by Nelson and of low qu
uality by Götzsche
e and included fo
or further
analysis10.
2.1.1.8.
Iden
ntified additional evidence
For diagnostic errors and over--diagnosis, this update was carrie
ed out in
o citations were excluded
e
July 2011 identtifying 10 citations. The majority of
on the basis of
o title and abstrract; 2 papers on
n diagnostic erro
ors were
retrieved in full and reviewed in more detail. On the basis of the full text,
ers are discussio
ons and
those two studies were excluded. Most pape
he two main SR4, 5.
comments on th
Ongoiing clinical trials
In
n addition to the database search
hes, the ClinicalT
Trials.gov website
e was
s
searched
for clinic
cal trials. The sea
arch terms ‘breastt neoplasm’ as well
w as
‘s
screening’ and ‘m
mammography’ were
w
used to search for studies.. The
m
majority
of search
h results (n=135
5) were ongoing trials. Two poten
ntially
re
elevant trials (NC
CT00963911, NC
CT00247442) werre identified but were
c
considered
as out of scope after receiving more iinformation on th
he full
p
protocol.
2
2.1.1.10.
Data extraction
e
Data from system
D
matic reviews and from trials were
e extracted into a data
e
extraction
table (D
DET) summarizin
ng key design fea
atures and resultts. All
d
data
extraction tab
ble are in Appendiix 1.6.
2.1.2. Descripttion of screening
2
g benefit
2
2.1.2.1.
Sourc
ces
In
n the years 196
60-1980, USA, Sweden,
S
Canada and United King
gdom
c
conducted
random
mized controlled trrials of mammogra
aphy screening. In
n US,
th
he HIP trial (N = 60 995) started
d in 1963. In Sw
weden, the Malmö
ö trial
(phase I and II, N = 60 076) started in 1976 and 1978
8, the Two county
y Trial
= 133 065) in 19
977-78, the Stock
kholm
(Kopparberg and Ostergötland, N=
n 1980 and finally
y the Göteborg tria
al (N= 51 611) in 1981.
trrial (N= 60 117) in
In
n Canada, the Na
ational Breast Sc
creening Trials (N
NBSS-1 and 2, N = 89
8
835)
were initiated
d in 1980. In Unite
ed Kingdom, the E
Edinburgh, trial sttarted
in
n 1979 in 1980 (N
N=44 268) and th
he UK Age Trial iin 1991 (trial limitted to
KCE Report 176
6
S
Screening
Breast Cancer
C
women aged 40-49 years)12. Numerous publlications and so
ome SR
ow available.
summarizing theirs results are no
ased on the SR
R (2002) commiss
sioned to assist the US
This part is ba
Preventive Serv
vices Task Force
e (USPTSF) and its update of 200
095,9 and
4
on the Cochran
ne SR . We ana
alysed more in de
etail one RCT named the
Swedish Two-C
County trial (Osttergötland) which
h was included by both
SR10,13,14.
Both reviews in
ncluded the same
e trials in their me
eta-analysis: the HIP
H trial,
Malmö I and II, the Two coun
nty trial, the NBS
SS trials (1 and 2), the
A
Trial. The Ed
dinburgh
Stockholm trial, the Göteborg trrial and the UK Age
d as poor quality b
by both authors an
nd excluded there
efore4, 9.
study was rated
Nelson updated
d the meta-analyssis from Humphrey
y9 to include new findings
about younger women (40-49 yyears of age). Th
herefore, we refe
er to the
blication for morta
ality analysis perrformed on wome
en aged
Humphrey pub
from 50 to 74 years. Götzsche
e4 performed firstt a meta-analysis
s among
4 years of age. T
Then he did a sep
parate analysis forr women
women 39 to 74
younger than 50
0 years and for w
women older than 50
5 years.
Two-County trrial
We analysed the Swedish T
Two-County trial in order to fin
nd more
ears). The Swedis
sh Twoinformation on our specific population (70-74 ye
he first eight rand
domized trials. We
W used
County trial is the largest of th
e publications tha
at describe this study.
s
We used the first
therefore three
publication of th
he initiator10, the p
publication of Nys
ström13 who was selected
s
by Nelson and the last publication of Tabar published in July 201114. The
wedish National Board
B
of
Two-County trial was commissioned by the Sw
W
and inclu
uded women in two Swedish counties:
c
Health and Welfare
Kopparberg and
d Östergötland. In
n 1977-78, 134 867 women aged 40
4 to 74
years were cluster-randomized
d by geographic area. They we
ere also
ocioeconomic stattus, urban or rura
al residency, and
d size of
stratified by so
cluster. Finally, 78 085 women
n were invited to
o the screening. Among
n aged 70-74 years in the screenin
ng group
those, they werre 10 568 women
and 7 462 in the
t
control group. At this age, wo
omen were invited
d to two
screening roun
nds with a screen
ning interval of 33
3 months. The trial
t
was
closed in 1984 after approximate
ely 7 years of scre
eening10.
23
In
n 2002, Nyström performed one review
r
of the Sw
wedish RCT’s including
th
he Malmö, Oste
ergötland, Stockh
holm, Göteborg trials. Results of
o the
K
Kopparberg
trial were
w
not available
e at this time. Thiss publication asse
essed
th
he age-dependen
ncy of the effectt of screening. T
The author calcu
ulated
m
mortality
relative risks
r
for consecutive 5-years age g
group based on re
esults
frrom the Ostergöttland trial. The median
m
follow-up time was 17.9 years.
y
U
Unfortunately,
with
hout the Kopparbe
erg part of the Sw
wedish trial, the nu
umber
o women 70 to 74
of
4 years of aged enrolled
e
was low ((approximately 50
000 in
e
each
group)13.
F
Finally,
we found one publication summarizing
s
long
g term data (29 years)
y
o mammographic
on
c screening effectt on mortality14.
T
Trials
quality and
d bias
A studies include
All
ed by Humphrey in
i 2002 and later by Nelson were rated
a fair5, 9. Götzs
as
sche assessed th
he randomization
n quality. This author
a
d
divided
his results
s on results based
d on adequately ra
andomized contro
ol trial
a results based on suboptimally randomized
and
r
contro
ol trial4.
N
Nevertheless,
the third meta-analy
yses were judged of high quality with
w a
lo
ow risk of bias (se
ee Appendix 1.5.1).
S
Some
publications
s based on The Swedish Two-Co
ounty reported va
arying
n
numbers
of women enrolled. To explain this variation
n, Nyström replied
d that
s
some
studies ana
alysed results by
y year-of-birth wh
hile some others used
e
exact
age at rand
domization13. Nev
vertheless, Götzscche assessed this
s trial
a suboptimally ra
as
andomized and likely to be biase
ed. He argued that for
O
Ostergötland,
a pu
ublic notary alloca
ated the clusters b
by tossing a coin while
w
witnesses
were prresent. Breast ca
ancer mortality in the control group
p was
a
almost
twice as high
h
in Kopparbe
erg compared to Ostergötland (0.0021
v
versus
0.0012, p = 0.02). The au
utopsy rate was 36% for all the TwoC
County
trial and ca
ause-of-death ass
sessments were n
not blinded4. Acco
ording
to
o that the validity
y of local end poin
nt committee data
a was criticized, a third
c
committee
(named
d consensus committee) reviewed the records conta
aining
a doubtful cause of
o death14.
24
2.1.2.2.
S
Screening
Breast Cancer
C
Bre
east cancer relatted mortality red
duction
For women age
ed 39 to 74 yearss and at approxim
mately 13 years of
o followup, the Humphrrey meta-analysiss (M-A)9 and the Cochrane
C
review4 showed
a significant re
eduction in breasst cancer mortalitty of 16% (Relative Risk
(RR) 0.84, 95%
% confidence inte
erval (CI) 0.77 to 0.91) and 19% (Relative
(
Risk (RR) 0.81,, 95% (CI) (0.74, 0
0.87) respectively
y.
For women ag
ged 39 to 74 years, the Review of Swedish rand
domized
control trial sho
owed a significan
nt reduction in breast cancer mortality at
15.8 years (me
edian follow up) o
of 21% (Relative Risk
R
(RR) 0.79, 95%
9
(CI)
0.70 to 0.89). This
T
study showed
d that the effect off breast cancer sc
creening
in terms of brreast cancer morrtality reduction varies according to age
range13.
For women age
ed at least 50 y a
at randomization, three
t
trials with adequate
a
randomization did not show a significant reduction in breast cancer
y
(Relative Risk (RR) 0.94, 95%
% (CI) 0.77 to 1.15). Four
mortality at 13 years
trials with suboptimal randomizzation showed a significant redu
uction in
m
(RR of 0
0.77 (95% CI 0.67
7 to 0.83)). The RR
R for all
breast cancer mortality
4
seven trials com
mbined was 0.77 ((95% CI 0.69 to 0.86)
0
.
The review of
o Swedish rand
domized control trial, applying a more
conservative de
etermination of ca
ause of death for women
w
aged at le
east 70 y
at randomizatio
on, did not show
w a significant reduction in breastt cancer
mortality at 17.4 years ((RR) 1.1
12, 95% (CI) 0.73
3 to 1.72)). Unforttunately,
mall (approximate
ely 5000 women in each
this age group was relatively sm
owered13. Consequently, we must conclude
c
group) and this study is underpo
t
age group5.
together with Nelson that data arre insufficient for this
2.1.2.3.
Dellay between scre
eening and spec
cific mortality red
duction
Tabar publishe
ed in July 2011 the last follow-up
p result (29-yearr) of the
Swedish Two-C
County Trial14. T
This publication modulated
m
breastt cancer
mortality reducttion in function of length of follow up.
u In this report both
b
data
issued from loc
cal end point com
mmittees and con
nsensus-based da
ata were
presented. The validity of local e
end point committe
ee data was criticized, we
c
data. For women age
ed 39 to 74 yea
ars, this
present here consensus
publication sho
owed specific morrtality reductions of 20% ((RR) 0.8
80, 95%
(CI) 0.62 to 1.0
05), 27% ((RR) 0
0.73, 95% (CI) 0..59 to 0.92), and 27% at
respectively 10
0, 15 and 20 to 2
29 years of follow
w up. In the sam
me time,
KCE Reportt 176
deaths from breas
d
st cancer preventted in the study g
group increased along
le
ength of follow-u
up. They were re
espectively 50, 9
99, 114, 122 and
d 126
d
deaths
prevented at 10, 15, 20, 25 and 29 years of ffollow-up for all wo
omen
in
ncluded in this study.
s
Author emp
phasized that bre
east cancer screening
p
prevents
deaths more
m
in the mediu
um to long term than in the imme
ediate
fu
uture. So most of the breast canc
cer deaths would have occurred (iin the
a
absence
of screen
ning) more than 10
0 years after rand
domization.
A
Authors
did not calculate mortaliity relative risks for each age group
g
s
separately.
Resultts presented are based on 133 06
65 women aged 40-74
4
(77 080 in the scre
eening group and 55 985 in the con
ntrol group), while
e they
w
were
10 568 wome
en aged 70-74 ye
ears in the screening group and 7 462
4 in
th
he control group
p. In Kopparberrg, cancers diag
gnosed after the
e two
s
screening
rounds in women aged 70-74 years and breast cancer deaths
frrom these cases were
w
still included
d in the results14.
A cited on previo
As
ous point, the grou
up of women aged
d 70-74 years included
in
n the Swedish Tw
wo-County Trial was
w relatively sma
all (approximately 5000
w
women
in each gro
oup) and this stud
dy is underpowere
ed13.
2
2.1.2.4.
All-cau
use mortality
The Cochrane SR
T
R has reported data on all-cause mortality. For wo
omen
a
aged
at least 50 y at randomization, two trials with ad
dequate randomiz
zation
(n=73654) did nott show a significant reduction in all-cause mortality at 13
y
years
(Relative Risk (RR) 1.00, 95%
% (CI) 0.95 to 1.0
04). The two trials
s with
s
suboptimal
rando
omization (n=982
261) also did no
ot show a significant
re
eduction in all-cause breast cance
er mortality (RR off 0.99 (95% CI 0..97 to
1.02))4.
U
Unfortunately
stud
dies did not have statistical power to detect an all-c
cause
m
mortality
reduction
n. According to th
hat disease speciific mortality is a small
frraction of all-caus
se mortality in cancer screening trrials, detect a mo
ortality
re
eduction would re
equire inclusion off millions of subjecct.
2
2.1.2.5.
Morbid
dity reduction
We found no data
W
a related to the cancer
c
related mo
orbidity in our selected
s
sources.
In other words, we do no
ot accept or reje
ect the hypothesis
s that
s
screening
reduces
s the morbidity of the
t breast cancerr disease.
KCE Report 176
6
S
Screening
Breast Cancer
C
2.1.3. Descrription of screening harms
2.1.3.1. Sou
urces
This part is bas
sed on the 5 SR se
elected in our main search4-8. As ex
xplained
in part 2.3.5, we
e updated those iin July 2011 startiing from the last literature
search date. Se
ee more details in appendix 1.4.
25
screening round). Conversely, false
s
e-negative mamm
mography results are a
little more commo
on among women aged 70 to 79
9 years (1.5 per 1000
w
women
per screen
ning round)5.
2
2.1.3.4.
Additio
onal diagnostic tests
t
SR written by Götzsche and N
Nelson are descrribed in point 3.1
1.1. The
n by Biesheuvel a
and Jorgensen6, 7 were focused on
o overreviews written
diagnosis and subsequently on
n overtreatment. Each author us
sed very
ods to address this issue. Biesheuvel analysed reports
different metho
issued from the first RCTs whiile Jorgensen an
nalysed data issu
ued from
zed screening prrogrammes. The review written by
b Virnig
publicly organiz
was focused on
n ductal carcinoma
a in situ (DCIS)8.
Rates of additiona
R
al imaging are rela
atively low among women aged 70 to 79
y
years
(64.03 per 1000 women pe
er screening round). Biopsy rates
s are
h
higher
among wo
omen aged 70 to
o 79 years (12.2 per 1000 women per
s
screening
round) than among youn
nger women. As expected, the nu
umber
o screen detected
of
d cancer is highes
st in this age grou
up. Results indicatte 6.5
s
screen-detected
in
nvasive cancer and 1.4 screen-de
etected DCIS per 1000
w
women
per screen
ning round. The BCSC
B
results indiccate that for every
y case
o invasive breast cancer detected by mammograph
of
hy screening in wo
omen
a
aged
70 to 79 yea
ars, 154 women have
h
additional mammography, 10 have
o
other
imaging test, and 2 have biopsies5.
2.1.3.3.
2
2.1.3.5.
2.1.3.2.
Stu
udy description
Perrformance of ma
ammography
The sensitivity of first mammog
graphy for women
n aged 70-74 ye
ears was
wo County trial. T
This includes ove
er-diagnosis and may be
81% in the Tw
difficult to interpret. This data cannot be applied to individual patients
ed for patient fa
actors (use of hormone
h
because they are not adjuste
herapy, mammog
graphic breast de
ensity), technical factors
replacement th
(quality of mam
mmography, number of mammogrraphic views) or provider
factors (the ex
xperience of radio
ologists and their propensity to la
abel the
results of an examination
e
abno
ormal)9. Provider factors may explain that
sensibility may
y vary between countries4. In the Two County trial,
t
the
specificity of a single mammogrraphic examinatio
on was 95.6% forr women
ears. This indicate
es that 4% of women
w
who did not
n have
aged 40-74 ye
cancer underw
went further diagn
nostic evaluation. The positive predictive
value of one-tim
me mammograph
hy was 12% for abnormal
a
results requiring
r
further evaluatiion and from 50% to 75% for ab
bnormal results requiring
r
biopsy. Positive
e predictive value increases with age
a and ranged fro
om 18%
to 20% among women 70 years of age or older9.
Nelson reporte
ed data from the Breast Cancer Surveillance Con
nsortium
(USA) BCSC fo
or regularly screen
ned women that are
a based on resu
ults from
a single screen
ning round. False
e-positive mammography results are less
common amon
ng women aged 70-79 years (68.8 per 1000 wom
men per
Over-d
diagnosis
Over-diagnosis off breast cancer at screening ma
O
ay be defined as
s the
d
detection
with scre
eening of cancer that would not ha
ave presented clin
nically
d
during
the woman
n’s lifetime (and th
herefore would no
ot be diagnosed in
i the
a
absence
of screen
ning)6.
N
Nelson
reported ra
ates of over-diagn
nosis varying from
m less than 1% to
o 30%
w
with
most from 1%
1 to 10%. She
e explained varia
ations by inclusio
on or
e
exclusion
of DCIS
S cases, by wheth
her cases are inciident or prevalentt, and
b age. She conclluded that the stu
by
udies are too hete
erogeneous to com
mbine
5
s
statistically
.
G
Götzsche
reported
d that the level of over-diagnosis w
was about 30% in
i the
R
RCT’s
that did no
ot introduce early screening in th
he control group, and
s
somewhat
larger in the sub optimally randomized tria
als before screening of
th
he control group. He found also a 40% to 60% inccrease in inciden
nce of
b
breast
cancer in observational
o
stud
dies performed in Australia, Europe
e and
U
USA
after beginnin
ng of the screenin
ng4.
B
Biesheuvel
analy
ysed publications
s issued from tthe first RCTs (New
Y
York/HIP,
Malm III, Two County, Canada
C
a and b, Stockholm, Göte
eborg,
E
Edinburgh)
and fro
om four populatio
on-based program
mme (Sweden, No
orway,
N
Netherlands
and Italy). He selected papers that a
attempted to estimate
o
over-detection
of invasive breast cancer by mam
mmography scree
ening.
26
S
Screening
Breast Cancer
C
Note that he did not include DCIS. He excluded potentially
y biased
B
were descriibed as: differen
nt breast cancerr risk in
publications. Bias
screened and unscreened
u
population, low particip
pation in screenin
ng group
and high partic
cipation in non-sccreening group, offering
o
screening
g to the
control group before
b
or during fo
ollow up, inapprop
priate adjustment for lead
time. After exc
clusion, he seleccted 22 estimates
s of over-detection from
several (some overlapping) sources. Publicatio
ons were categorrized as
e-incidence or incidence-rate methods
m
being based on cumulative
t
are in appe
cluding biased stu
udies as
endix 1.4.3). Exc
(definitions of terms
described before, he selected tthe least biased over-detection
o
es
stimates.
S cases, over-dettection ranged fro
om 7% to 21% forr women
Excluding DCIS
aged 60–69 yea
ars6.
Jorgensen ana
alysed data issued from public
cly organized sc
creening
programmes. He
H selected pape
ers that published trends in incid
dence of
breast cancer before and affter the introduction of mamm
mography
e that when data were present, DC
CIS were included
d. If not,
screening. Note
he estimated that
t
they would ccontribute to 10%
% of the diagnos
ses in a
screened population. After exclu
usion of the impllementation phase of the
ast seven years
s before
screening, he compared data covering at lea
y
after scree
ening in
screening with data covering at least seven years
n screened age
e groups. The most common age-range for
screened and non
mammography screening progra
ammes was 50-69 years. No data specific
e increase in incid
dence of
for women aged 70 to 79 years are available. The
elated to the inttroduction of sc
creening.
breast cancer was closely re
ase was compen
nsated for by a drop in
Surprisingly, litttle of this increa
incidence of breast cancer in women older than 70 years. Jo
orgensen
for invasive cance
er was 35%. The
e rate of
calculated that over-diagnosis fo
n this meta-analys
sis (95%
over-diagnosis including DCIS ccases was 52% in
CI 46% to 58%)7.
sheuvel or by Jo
orgensen
Discrepancies between results reported by Bies
ot of controversial discussions.
have led to a lo
The approach Biesheuvel
B
et al. tto adjusting for lea
ad time was conte
ested by
Zahl, Jorgense
en and Götzche (2008), who stated that their estimations
were substantia
ally downwardly biased, due to over-adjustment,
o
u
use
of a
hypothetical inc
crease in incidencce based on theoretical models and use of
KCE Reportt 176
ong term follow
w up data that are considerablyy diluted. They also
lo
considered estima
c
ation unhelpfully wide.
w
J
Jorgensen
& Gö
ötzsche used line
ear regression tto compare obse
erved
in
ncidence with a in an (hypothettical) population that did not und
dergo
s
screening.
They assume
a
a linear in
ncrease extrapola
ated from prescreening
trrends, following the same pattern as the linear tren
nd observed in wo
omen
to
oo young to be sc
creened. It is difficult to judge if thiis assumption hollds or
n
not,
the graphs the authors prresent show no
on-linear increase
es in
in
ncidences before
e screening was introduced in the
e UK and Norwa
ay for
w
whom
no explanattion was given.
2
2.1.3.6.
DCIS
Historically, DCIS
H
S was rare and diagnosed by ssurgical removal of a
s
suspicious
breast mass. Since the wide use of mammograph
hy, a
in
ncreasing numbers of patients werre diagnosed with
h DCIS. The prog
gnosis
o the disease is excellent. Maass
of
s reported data isssued from the SEER
S
d
database
(Surveillance, Epidemiolo
ogy and End Re
esults database of
o the
U
United
States National Cancer Ins
stitute). Those da
ata showed a 10
0-year
s
survival
rate of 96.6%
9
for cases
s between 1978 and 1983, whe
en no
s
screening
was pe
erformed. The rate
e was 98.1% bettween 1984 and 1989,
w
when
screening was
w performed3, 15.
R
Recent
changes in
i DCIS incidenc
ce in USA were e
emphasized by Virnig.
V
T
This
author perfo
ormed a SR on incidence, treatm
ment and outcomes of
D
DCIS
in name of Agency for Healthcare Research
h and Quality (AH
HRQ).
S
She
included 63 publications ad
ddressing inciden
nce for analysis. She
c
compared
data obtained before th
he screening (19
973-1975) with cu
urrent
c
century
data collected in US where
e screening is com
mmon. DCIS incid
dence
ro
ose there from 1.87 per 100 000 in 1973–1975 to
o 32.5 per 100 000
0
in
2
2004.
Incidence in
ncreased most in women older tha
an 50 years. Incre
eased
u
use
of mammogrraphy may explain some but nott all of this incre
eased
in
ncidence8.
KCE Report 176
6
2.1.3.7.
S
Screening
Breast Cancer
C
Ove
ertreatment
Götzsche reported that the num
mber of mastecto
omies and lumpe
ectomies
T
trials with adequate
a
was significantlly larger in the sccreened groups. Three
randomization showed a sign
nificant increase
e in mastectomiies and
(
Risk (RR
R) 1.31, 95% (CI)) 1.22 to 1.42). Tw
wo trials
lumpectomies (Relative
with suboptimal randomization sshowed the same increase in interv
ventions
5% CI 1.26 to 1.61
1)). The RR for alll five trials combined was
(RR of 1.42 (95
1.35 (95% CI 1.26 to 1.44)4.
Based on recent data from the UK Breast Scree
ening Programme
e, Dixon
mbers of patients
s with DCIS. In 1998/99
emphasized the increasing num
proximately 1500 cases, but in 200
07/08 there were close to
there were app
3500 cases. Although,
A
most DCIS cases ma
ay be treat by breastconserving surrgery, the percen
ntage of patients
s being treated with
w
this
method has rem
mained constant at 30% during this period. Becaus
se of the
increasing incid
dence of DCIS tre
eatments, the abs
solute numbers off women
having mastecttomies has increased from just und
der 500 in 1998/99
9 to over
1
900 in 2007/0811
.
2.1.4.
Scree
ening conditions
The sojourn tim
me (ST) is the avverage duration of
o the preclinical screendetectable phase. Estimation off sojourn time ca
an be performed by from
matical estimates or using mic
crosimulation tec
chniques
simple mathem
(mainly Markov
v Models)12. Sojou
urn time provides an absolute uppe
er limit to
the lead time obtainable. If the sojourn time is long, the maximum
m
nding long16. A lo
onger sojourn time
e results
attainable lead time is correspon
ber of additional breast cancer detected,
d
more liife-years
in higher numb
gained and high
her number of yea
ars with cancer du
ue to lead-time17.
2.1.4.1.
Lite
erature search
In a first stage, studies assesssing sojourn tim
me were searche
ed. Ovid
c
from 19
948 to October Week
W
1 2011. Th
he main
Medline was consulted
search terms (MESH) were: Breast Neoplasm
ms/ Mass Screening/ or
was included in frree text. The sea
arch was
Mammography//. Sojourn time w
limited to paperrs written in Engliish, Dutch, Frenc
ch, or German. Re
eference
lists of the sele
ected studies were
e checked for add
ditional relevant citations.
c
See more details in appendix 1.4
4.4.
27
Selection criteria
S
a
A retrieved refe
All
erences were as
ssessed against pre-defined inclusion
c
criteria
(in terms of
o population, inte
ervention, outcom
mes, and design-T
Table
1) in a two-step procedure: initial assessment of the title, abstractt and
k
keywords;
followe
ed by full-text as
ssessment of the
e selected refere
ences.
E
Estimation
of sojjourn time not based
b
on data were excluded. After
e
excluding
of 3 du
uplicates, 40 unique citations we
ere identified from
m the
d
databases.
Of this
s total of 40 refe
erences, 23 did n
not meet the inclusion
c
criteria
based on title and abstract evaluation. Am
mong the 17 cita
ations
re
etained for full-tex
xt assessment, 6 did not fulfill the population criteria18-23
a
and
1 did not fulfill the outcom
me criteria24. Fina
ally, 10 studies were
16, 17, 25-32
re
etained
O search was based
Our
b
on ST dura
ation estimations as search. We found
f
s
several
publication
ns were ST estim
mations were issue
ed from others sttudies
c
cited
as references by the author. For
F example, Zappa in 200332referrred to
29
d
data
published by
y Tabar in 1995 . Duffy in 200526 referred also to those
29
d
data
. Therefore, we used origina
al publications. If one author published
tw
wo or more articles based on the
t
same data, we choose the most
30, 31
a
accurate
for our study
s
. Finally, 7 publications arre summarized in
n data
e
extraction
table (se
ee appendix 1.6.7
7).
2
2.1.4.2.
Resultts
Sojourn times ca
S
alculated on RCT
T’s data
W found 4 studies based on the results of the Tw
We
wo- County Trial. The
T
TwoCounty Tria
al is described in
n chapter 2 (poiint 2.2.1.1.)10, 13. First
e
estimates
of sojou
urn time publishe
ed by Tabar and Duffy were base
ed on
a
approximately
the same data. Both
h authors used th
he same Markov chain
m
model,
but results
s were not the sam
me. Shen underlin
ned that the differrence
25, 29
in
n estimates publis
shed by the two authors
a
may be caused by diffferent
s
statistical
methods
s or by discrepanc
cy in the data. Shen applied his rec
cently
d
developed
statistic
cal methods base
ed on the maximu
um likelihood estim
mates
to
o data from the Two
T
County Triall. Authors estima
ated the sensitivitiies of
e
early
detection modalities
m
as 0.92
2 (SD, 0.09) and the mean ST as
a 4.4
y
years
(SD, 0.76)27.
28
S
Screening
Breast Cancer
C
Sojourn times calculated on sc
creening program
mmes data
Spratt estimate
ed the duration of breast cancer be
efore detection by dividing
prevalence rate
es at first screenin
ng round by incide
ence rates in the following
f
years. Thereforre, he used data ffrom 10 000 wome
en aged 35 to 70y
y at start
included in the Breast Cance
er Detection and
d Demonstration Project
d that sojourn time
e ranged
(Louisville). Forr women aged 70-74, he estimated
between 2.5 y to
t 3.8 y28.
Fracheboud co
ompared the resu
ults of the Dutch breast cancer sc
creening
programme for women aged 70--75 with the hypotthesis developed by Boer
optimistic and pes
ssimistic assumpttions for
in 1995. Boer had described o
SCAN model. Op
ptimistic assumpttion assumed no
o further
use in his MIS
increase in pre
eclinical duration
n of breast cancer after 65years of age
although pessim
mistic assumption
n assumed a furth
her increase in prreclinical
duration with age
a 33. Based on 187 207 screenin
ng examinations (women
aged 70-74 years), Fracheboud
d found that dete
ection rates in bo
oth initial
nt screens increa
ased steadily witth age and got close to
and subsequen
assumption which assume a continuously increas
sing sojourn time
e beyond
b
tumours le
ead to a
the age of 69. This increasing sojourn time of breast
e in detection of cancers, but also to
t more life- years
s in lead
strong increase
time17.
Weedon constrructed one inventive solution for sc
creening program
mme who
do not have fu
ull registration off interval cancers
s or where oppo
ortunistic
screening is common. Although
h Norwegian reg
gistration is of ve
ery high
nce data from the
e first screening round, interval between
b
quality, inciden
screening exam
mination or registra
ation of interval ca
ancer may be insufficient.
Therefore, he replaced data la
acking by data is
ssued from questtionnaire
5
women in the Norwegian Breast
B
Cancer Sc
creening
send to 336 533
Programme (NBCSP). This new
w approach gave estimation of MS
ST to 6.9
en aged 60-69 yea
ars, although STS
S was estimated to
o 60%30.
years for wome
2.1.4.3.
2
2.1.5.
KCE Reportt 176
Key data
a
D
Data
issued from literature
l
search are
a summarized in
n table 2.1.
T
Table
2.1: Data is
ssued from clinic
cal literature reviiew
Question 1: Sho
Q
ould breast canc
cer organized sc
creening extende
ed in
w
women
between 70 and 74 years?
?
P
Population
Women be
etween 70-74 yyears of age without
breast canc
cer and without p
particular risk of breast
b
cancer.
In
ntervention
Organized screening with mammography
C
Comparison
No organized screening
O
Outcomes:
M
Mortality
(specific)
For women
n >50 y at rando
omization, the sp
pecific
mortality re
eduction after a fo
ollow-up of 13 yea
ars is
23% (RR: 0.77, (CI) 0.69 to 0.86). In the Two
al, specific mortality reduction rea
ach at
County tria
significant reduction
r
of 27% (RR: 0.73, (CI) 0.59 to
0.92) at 15
1 years of follo
ow up and incre
eases
afterwards..
M
Mortality
(all caus
se)
Studies did
d not have statistical power to dete
ect an
all-cause mortality
m
reduction.
F
FP
68.8 per 1000 women age
ed 70 to 79 yearrs per
r
(BCSC-USA
A)
screening round
F
FN
1.5 per 10
000 women aged
d 70 to 79 years
s per
screening round
r
(BCSC-USA
A)
A
Additional
imagin
ng
64.03 per 1000 women age
ed 70 to 79 yearrs per
r
(BCSC-USA
A)
screening round
B
Biopsy
12.2 per 1000 women age
ed 70 to 79 yearrs per
r
(BCSC-USA
A)
screening round
Discussion
Most estimates
s of sojourn time have been ba
ased on Models (mainly
Markov chain models). Such m
models assume a chronological stepwise
s
er. Unfortunately, it remains unkno
own whether canc
cer really
growth of cance
develop accord
ding to a chrono
ological sequence
e. Estimations of sojourn
time must consequently be interp
preted with caution.
KCE Report 176
6
S
Screening
Breast Cancer
C
29
DCIS
1.4 scre
een-detected DCIS
S per 1000 wome
en aged
70 to 79
9 years per screen
ning round (BCSC
C-USA)
2
2.2.
Review of
o modeling stud
dies
Over-diagnosis
Over-de
etection (excluding DCIS cases), ranged
from (7%
% to 21%) to 35
5% (no data spe
ecific for
women a
aged 70 to 79 yea
ars are available)..
Over-treatmen
nt
The num
mber of mastecto
omies and lumpe
ectomies
was sig
gnificantly larger in the screened groups
(RR:1.35
5 (95% CI 1.26 to
o 1.44).
In
n a first stage, ran
ndomized clinical trials analysing th
he impact of screening
o morbidity and mortality
on
m
were sea
arched (see abovve). Then, becaus
se the
e
effectiveness
of sc
creening require a lot of information
n from a wide ran
nge of
s
sources
to corre
ectly inform decision makers, modeling studies were
35
s
searched
.
M
Medline,
Embase,, NHS EED and Econlit databasess were consulted from
J
January
2000 up to
t September 2011 (see appendixx 2.1). The search
h was
limited to papers written in English
h, Dutch, French,, Spanish, or Gerrman.
R
Reference
lists of the selected studies were checked
d for additional relevant
c
citations.
T keywords use
The
ed and the results
s are detailed in appendix 2.1. The main
s
search
terms (MES
SH) were:
2.1.6.
Concllusion
At this age gro
oup, performance
e of mammograp
phy is high and rates of
additional imag
ging are relativelyy low. Breast canc
cer screening ach
hieves a
specific mortality reduction of 23% to 27% according to autho
ors. This
ear in the first ye
ears after screeniing. The
mortality reduction did not appe
gnificant before 10
1 years
specific mortaliity reduction is not statistically sig
after screening
g ((RR) 0.80, (CI) 0.62 to 1.05). Breast cancer mortality
m
reduction must be put in perspecctive with life-expe
ectancy for this ag
ge-group
in our country.
elated to quality of life raises questions
On the other hand, aspects re
cussion of the ben
nefit and harms of breast cancer sc
creening
pertinent to disc
in this age-grou
up. First, over-diag
gnosis being an in
nevitable consequ
uence of
cancer screening, the risk of overtreatment pers
sists. Secondly, the
t
lead
ough difficult to esstimate, may be crucial for older women.
time bias altho
Screening diagnosed breast can
ncer and consecu
utive treatment ma
ay mean
h condition” some years earlier than
n clinical
the end of “the life in good health
ast cancer34.
diagnosed brea
2
2.2.1.
Literaturre search strateg
gy
•
Breast Neopla
asms; and
•
Mass Screening or Early Detec
ction of Cancer ; a
and
•
hy; and
Mammograph
2
2.2.2.
Selection
n criteria
All retrieved refe
A
erences were as
ssessed against pre-defined sele
ection
c
criteria
(in terms of
o population, inte
ervention, outcome
es, and design - Table
T
2
2.2.)
in a two-step
p procedure: initia
al assessment off the title, abstrac
ct and
k
keywords;
followe
ed by full-text ass
sessment of the sselected referenc
ces. It
s
should
be noted that studies assessing screening
g techniques (suc
ch as
d
digital
mammography) were exclude
ed because such topic was investig
gated
in
n KCE report 1722.
30
S
Screening
Breast Cancer
C
Table 2.2: Sele
ection criteria
Population
Intervention
T
Table
2.3: Modeliing studies exclu
uded after full-tex
xt assessment
Inclusion crite
eria
Ex
xclusion criteria
E
Exclusion
criteria
a
Studies
caucasian wom
men without
breast cancer and without
particular risk
Otther (e.g. woman
n at risk,
As
sian women, etc.)
P
Population
Messecar 2000;
2
Wen 200560, 61.
Screening mam
mmography
Otther,
including
ma
ammography tec
chniques
(e.g. digital mammo
ography)
O
Outcome
Outcomes
Morbidity and
d Mortality
(e.g. LYG and Q
QALYs)
Otther outcomes (e
e.g. over
dia
agnosis)
Design
Modeling studie
es
Otther designs
LYG: life-year ga
ained; QALY: Qualityy-adjusted life-year gained
2.2.3.
KCE Reportt 176
Quantity of research a
available
After excluding 195 duplicates, 1058 unique citattions were identiffied from
g did not allow us to identify ad
dditional
the databases.. Hand searching
citations. Of this total of 1058 re
eferences, 1016 did
d not meet the inclusion
criteria based on title and absstract evaluation. Among the 42 citations
he population critteria and
retained for full-text assessmentt, 2 did not fulfill th
odeling publicatio
ons were
15 did not fulfill the design criterria. Finally, 25 mo
erning 6 models d
developed by modeling groups inv
volved in
retained, conce
CISNET, 2 app
plications of these models on differe
ent context and 7 models
developed by other groups or authors, as som
me models have several
3
. The flow ch
hart of this selec
ction is presented
d in the
publications17, 36-59
appendix 2.2.
In
ntervention
D
Design
Advisory Committee
C
on B
Breast Cancer 2006;
2
Anonymou
us 2000; Barratt 2
2002a; Barratt 20
002b;
Bonneux 2009;
2
Caplan 2001; Carney 2007
7; De
Koning 20
000; Feuer 200
04; Grivegnee 2001;
2
Habbema 2006; Mandelblattt 2003; Prevost 2000;
2
auch 2000, Xu 200
0062-76.
Rautenstra
2.2.4. Selected
2
d studies
2
2.2.4.1.
The CISNET
C
Project
The Cancer Interrvention and Surrveillance Modelin
T
ng Network (CIS
SNET)
(http://cisnet.cance
er.gov) is a con
nsortium of National Cancer Ins
stitute
ose focus is mo
odeling the impa
act of
(NCI)-sponsored investigators who
c
cancer
control inte
erventions on population trends in incidence and mo
ortality
fo
or breast cancer. These models arre also used to prroject future trends
s and
to
o help determine optimal cance
er control strateg
gies40. Seven grroups
d
developed
their own
o
breast cancer models spann
ning a wide rang
ge of
m
modeling
philosop
phies: The Univerrsity of Texas M.. D. Anderson Ca
ancer
C
Center
model37, University
U
of Wisc
consin model, Ge
eorgetown47, Erasmus
5
44
(MISCAN) model57
, Dana-Farber model
m
Universityy of Rochester mo
odel43
51
a Stanford model ).
and
T
The
seven models were first used to assess the relative and abs
solute
c
contributions
of screening mammo
ography and adju
uvant treatment to the
re
eduction in breast-cancer mortaliity in the United States from 197
75 to
77
2
2000
. Mandelbla
att et all48 used 6 of those CISNET models to prrovide
e
estimates
of pote
ential benefits an
nd harms of mam
mmography screening
u
under
different scrreening schedules
s. One of the 7 mo
odels, the Univers
sity of
KCE Report 176
6
S
Screening
Breast Cancer
C
Texas M. D. Anderson
A
Cancer Center model37 was not used as
s it was
purely descriptive.
The models we
ere developed byy different groups but not indepe
endently,
they were com
mpared, discusse
ed and adapted during the deve
elopment
process, they also
a
used a comm
mon set of variab
bles and inputs, based on
US datasets BCSC
B
(Breast Ca
ancer Surveillanc
ce Consortium), SEER
S
9
(Surveillance, epidemiology
e
and
d end results), Co
onnecticut Tumorr registry
and the Berkele
ey mortality Datab
base.
A detailed dis
scussion of each
h of this models
s can be found
d in the
publications and
d on the CISNET website, we will not
n discuss each model
m
in
detail, but sum
mmarize the poole
ed comparison off Mandelblatt et al.
a 48 and
discuss the ma
ain limitations an
nd implications fo
or our research question.
q
The models es
stimated a large
e number of sce
enarios, but we will
w only
present the re
esults of the partt relevant to ourr research questtion, the
comparison of a screening pollicy screening ag
ge 50-69 to a sc
creening
g age 50-74.
policy screening
Feuer et al.40 identifies two d
dimensions to ch
haracterize the types
t
of
surveillance mo
odels used here. The first dimen
nsion incorporate
es micro
simulation mod
dels at one end o
of the spectrum, where
w
individuals are run
through the model one at a tiime, where at each transition a random
dividual life histo
ories are genera
ated, to
number is generated and ind
mechanistic orr analytic modells, where a sett of analytically derived
equations desc
cribe the relation
nships between key
k
health states
s and/or
tumor growth and
a
metastasis. T
The University off Texas M. D. Anderson
A
Cancer Centerr, University of Wisconsin, Geo
orgetown, and Erasmus
E
models could be characterized as micro simula
ation models; the
e Danac
be characte
erized as analytic
c; and the remain
ning two
Farber model could
models (University of Rocheste
er and Stanford)) could be descrribed as
d dimension off model
having some aspects of each. The second
n runs from bio
ologic, where th
he model goes beyond
characterization
observable qua
antities to model tthe underlying dis
sease onset, grow
wth, and
progression of disease, to epid
demiologic, wherre only a portion
n of the
ually the observab
ble portion).
disease process is modeled (usu
art with estimatess of breast cance
er incidence and mortality
m
The models sta
trends without screening and ttreatment and th
hen look at the effect
e
of
a improvementss in survival assoc
ciated with treatm
ment.
screening use and
31
Breast cancer is assumed to ha
B
ave a preclinical,, screening-detec
ctable
p
period
(sojourn time) and a clinical detection po
oint. On the bas
sis of
m
mammography
se
ensitivity (or thresholds of detection
n), screening iden
ntifies
d
disease
in the prreclinical screenin
ng-detection perio
od and results in the
id
dentification of ea
arlier-stage or smaller tumors than might be identifie
ed by
c
clinical
detection, resulting in redu
uction in breast ccancer mortality. Age,
e
estrogen
receptor status, and tumor size– or stage–sspecific treatment have
in
ndependent effec
cts on mortality. Women
W
can die o
of breast cancer or of
o
other
causes. as mentioned before
e, the 6 models use a common set
s of
a
age-specific
varia
ables for breast cancer incidence
e, mammography
y test
c
characteristics,
tre
eatment algorithm
ms and effects, a
and non-breast ca
ancer
c
competing
causes
s of death. On the other hand, unob
bserved variables such
a preclinical dete
as
ectable times (sojourn time), lead time, dwell time within
w
s
stages
of disease
e, were in these models estimated
d intermediate ou
utputs
th
hat followed from the model structture and assumpttions concerning tumor
t
g
growth.
T
The
stage distribu
utions in unscree
ened versus scree
ened women in these
t
m
models
were also
o intermediate outcomes, this in ccontrast to some other
m
models
that use th
his observable va
ariable as input. A
As end output from
m the
m
model
reductions in mortality, life ye
ears gained were
e calculated, no QALYs
Q
w
were
used. The ha
armful effects fals
se positive mamm
mograms, unnece
essary
b
biopsies
and overr diagnosis follow
wed from the model, also here no direct
o
observed
input wa
as used, no attempt was made to q
quantify those harrms in
te
erms of QALYs. Morbidity
M
associa
ated with surgery for screening-detected
d
disease
or decre
ements in quality
y of life associatted with false-po
ositive
re
esults living with
h earlier knowle
edge of a cance
er diagnosis or over
d
diagnosis
was nott considered, whic
ch makes the mod
dels less useful fo
or our
p
purposes.
T
Table
2.4 gives the results of the
e different modelss in terms of mo
ortality
re
eduction and yea
ars of life gained for
f the different m
models. Gains are fairly
limited and there is some variabilitty between mode
els, with number years
g
gained
per 1000 women screened
d ranging from 9 to 17 and numb
ber of
d
deaths
averted ran
nging from 4 to 6.
T
This
class of mode
els relies heavily on
o unobservable vvariables, and as most
m
models
are indiv
vidual bases the
ey are not alwa
ays very transpa
arent.
In
ndependent validation was made difficult because results from trials
s and
32
S
Screening
Breast Cancer
C
the main US breast cancer rregistries were used
u
to parameterize or
m
Model outp
puts are similar to
o the results from
m RCT’s
calibrate the model.
and some observational studiess, but this does not say much ab
bout the
dies were partly used to
validity of the model as data from those stud
odel.
calibrate the mo
Table 2.4: res
sults of the diifferent models in terms of mortality
m
reduction and years of life ga
ained per 1000 women
w
screened
d for the
els
different mode
Model
Mortality (specific) re
eduction over the whole
period in %
Screening in agegroup 50-69
Screening in agegroup 50-74
eduction screening in
Incremental mortality re
agegroup 50-74 compa
ared to screening in
agegroup 50-69
p 1000 women
Years of life Gained per
screened
Screening in agegroup 50-69
Screening in agegroup 50-74
Incremental years of liffe gained screening in
agegroup 50-74 compa
ared to screening in
agegroup 50-69
Incremental days of liife gained per women
screened
p 50-74 compared to
Screening in agegroup
screening in agegroup 50-69 women screened
D
E
G
M
S
W
16
22
23
27
17
21
16
21
15
20
23
28
6
4
4
5
5
5
88
106
107
116
111
128
82
96
99
121
84
95
18
9
17
14
22
11
women screened for a biannual scrreening in the age
w
e group 50-74, with an
in
ncremental beneffit for biannual screening
s
50- 74
4 of 1.7% in term
ms of
m
mortality
and 2 liffe years gained per
p 1000 women screened. As au
uthors
h
had
no choice th
han to use US data for most ke
ey variables one
e can
q
question
in what degree this can really be called an adaptation to the
C
Catalan
context. Carles
C
et al, 2011
138 finally used th
he results of Rue et al
58
a Vilaprinyo et al
and
a to do a cost effectiveness
e
analysis, including QA
ALYs.
T
They
found 3990 life years gained
d for a cohort of 100 000 women for a
b
biannual
screening
g in the age group 50-74, with an incremental bene
efit for
b
biannual
screening 50- 74 of 299 life years gained
d per 100 000 wo
omen.
T
They
found 3891 QALYs gained per 100 000 wo
omen screened with
w
a
b
biannual
screening
g in the age group 50-74, with an incremental bene
efit for
b
biannual
screening 50- 74 of 277 life years gained
d per 100 000 wo
omen
c
compared
to a sch
hedule 50-69. The
ey did not report tthe QALYs gained
d with
e
extending
the scrreening to 50-74 from 50 -69, ass it was dominate
ed by
s
screening
from 45
5- 69, but reporte
ed that 186 QAL
LYs per 100 000 were
g
gained
by extendin
ng the screening to 45-74 from 45 -69. Interestingly, they
d
did
not incorpora
ate the results of Vilaprinyo ett al,200958 into their
c
calculations,
but used
u
US survivall data. They did not take into account
o
over
diagnosis.
2
2.2.4.2.
6,6
3,3
6,2
5,1
8,0
4,0
Model group abb
breviations: D _ Dan
na-Farber Cancer In
nstitute; E _ Erasmu
us
Medical Center; G _ Georgetown Un
niversity; M _ M.D. Anderson
A
Cancer Center;
C
S
_Stanford Univerrsity; W _ Universityy of Wisconsin/Harv
vard
Stout et al 200
0656 used the Wissconsin model to
o do a cost effec
ctiveness
analysis, includ
ding the use of QA
ALYs, but compa
arisons of the age
e groups
50-74 with age groups 50 - 69 were not made.
Rue et al.55 ad
dapted de Dana-F
Farber Cancer Institute model of Lee
L
and
Zeelen44 to datta in Catalonia. B
Because there wa
as insufficient info
ormation
on Catalan surv
vival they combin
ned the survival da
ata from the SEE
ER in the
US with Catalan data in a prrevious publicatio
on of Vilaprinyo, 200958.
milar to the ones Lee & Zeelen originally
o
Obtained results were very sim
ality reduction of 21% and 131 life
e years gained per
p 1000
found, a morta
KCE Reportt 176
Modells not related or not using CISNE
ET methodology
y
3 78
Carter et al, 200539,
C
developed a micro simulation model based on tumor
t
g
growth
using main
nly SEER data. Th
he model lacks crredibility though mainly
m
b
because
of unrealistic assumptions
s concerning stag
ge specific surviva
al, as
th
hey assume a fix
xed survival of 2 years
y
for stage 4 and complete cure for
s
stages
1, 2 and 3. This leads to con
nsiderably higher years of life gaine
ed for
s
screening
than otther models but is in absolute con
ntradiction to wha
at we
k
know
about stage specific survival.
R
Rojnik
et al, 2008 produced a time dependent
d
Marko
ov model with 4 stages,
D
DCIS,
local, regio
onal and distant. Overall model structure was desc
cribed
b details on how
but
w the model was parameterized
p
are
e lacking so we ca
annot
ju
udge how this wa
as done or if ass
sumptions were rreasonable. They
y only
re
eport ICERs so we
w have no inform
mation on assumed gains in Life Years
Y
G
Gained
and QALY
Ys.
KCE Report 176
6
S
Screening
Breast Cancer
C
Neeser et al developed
d
a sim
mple Markov mod
del comparing orrganizes
screening with a coverage of 70% with opporttunistic screening
g with a
0%. They assumed that the orga
anized screening reduces
coverage of 20
breast cancer mortality
m
with 15%
% based on the IARC handbook, but it is
unclear how th
hey come to thiss figure as IARC
C postulates a re
eduction
ranging from 5 to 20%. They ca
alculated the yea
ars of life gained for a 10
ng beginning at 70 (they evaluatted other schedu
ules not
years screenin
relevant for ou
ur research quesstion as well. They found that orrganized
screening would save 41 lives p
per 100 000 and add 0.008 life ye
ears (2.9
men screened for 10 years. The model
m
is somewha
at overly
days) per wom
simplistic by not
n taking into account lead time
e but applying assumed
a
reductions imm
mediately. No QA
ALYs were used and effects on morbidity
m
was not taken into account.
Rauner et al, 2010
2
developed a
an ant colonizatio
on optimization model but
only evaluated the effect of scrreening amongst women 50-70 and
a
their
ental model is nott useful for our pu
urposes. It is also
o unclear
rather experime
how they actually modeled stage
e specific survival..
46
Mahnken et al,, 2008 develope
ed a method to adjust
a
for lead tim
me bias,
length bias and
d over-detection and applied this to SEER data, but provided
p
only adjusted Hazard
H
ratio’s.
Rijnsburger et al, 200453 use
ed the MISCAN micro-simulation
n model
t
Rotterdam57 (see above) to replicate
r
the data
a of the
developed by the
Canadian CNBSS-2 trial on brea
ast cancer screen
ning among women aged
ur purposes.
50–59, so their findings are not rreally useful for ou
36
2
constructe
ed a Markov mo
odel for two hypothetical
Barratt et al 2005
cohorts, with one
o
cohort wome
en undergoing bie
ennial screening and the
other not, assuming 100% particcipation. Within th
his model, they ev
valuated
o women over 70
0 years old underg
going 10 years of biennial
the outcomes of
screening. The
ey assume a 37%
% mortality reduc
ction, adjusting the
t
25%
reduction from for non compliance, and assum
me that benefit accrues
ximal level over first five years afte
er starting screen
ning and
linearly to max
that benefit de
eclines linearly to
o nothing over five
f
years after stopping
s
screening. For women who conttinue screening fo
or 10 years after the age
wer women per thousand die from breast cancer than in
of 70s, two few
women who sto
op screening (sixx v eight deaths from
f
breast canc
cer). The
number of diagnoses of breast ccancer in screened women is about 41 and
33
he number in uns
screened women about 26. assum
ming a risk reductiion of
th
50% brings the nu
5
umber of deaths in the screened g
group down 6.2 to
o 5.1.
T
This
simple mode
el has the advanta
age of transparen
ncy, but does nott take
in
nto account the efffects of lead time
e and stage-shifts on morbidity.
2
2.2.5.
Conclusiion
Models described are give useful in
M
nsights and eleme
ents but it is diffic
cult to
a
adapt
them to the Belgian situation
n as we do not ha
ave the necessary
y data
to
o parameterize th
hem. The CISNET
T models give a m
modest gain in ye
ear of
life between 9 an 22
2 years per 1000
0 women screene
ed.
2
2.3.
Review of
o quality of life studies
Because breast cancer
B
c
screening
g programs are expected to hav
ve an
im
mpact on the qu
uality of life (QoL
L) of the patientss, models with a oned
dimensional
health
h-outcome measu
ure in terms of su
urvival are not en
nough
in
nformative. It is important to take
e into account all the multidimens
sional
h
health
outcomes in the assessmen
nt of breast cance
er screening progrrams.
T value these multidimensional ou
To
utcomes into a single measure, qu
ualitya
adjusted
life-year (QALY) must be
b used. QALYs permit to adjus
st the
e
expected
length of life by the health-related q
quality of life. These
T
a
adjustments
are made
m
using utilitie
es derived from iindividuals’ preferrence
fo
or different health
h states.
D
Determination
of utility values, needed for the ccalculation of QA
ALYs,
re
equires two steps
s:
1. The health state description. According to the
e pharmaco-econ
nomic
ealth Care Know
wledge Centre (K
KCE),
guidelines off the Belgian He
s should be des
scribed on a sta
andardized descrriptive
health states
system. Ideallly, the descriptio
on should be don
ne by Belgian pa
atients
using a gene
eric descriptive system,
s
such as the EQ-5D. If health
h
states descrriptions from Belgian
B
patients are not available,
descriptions frrom similar patien
nts in other countrries may be used7
79.
34
S
Screening
Breast Cancer
C
2.
The valuattion of these he
ealth states. Acco
ording to the pharmacoeconomic guidelines
g
of the K
KCE, health state
e values should be
e valued
on a 0 (=v
value for death) to
o 1 (=value for perfect
p
health) sca
ale by a
representa
ative sample of th
he general public
c. Ideally, they sh
hould be
valued by the Belgian popu
ulation but if no original Belgian data
d
are
m other countrie
es can be use
ed and
collected, valuations from
79.
discussed7
In this section, the availability a
and the quality of
o published utility
y values
ase due to breas
st cancer (screen
ning and
describing the burden of disea
ssessed.
treatment) is as
2.3.1. Metho
ods
2.3.1.1. Lite
erature search sttrategy
Electronic data
abases were con
nsulted for origin
nal publications on
o utility
estimates for different health states associatted with breast cancer
matic searches were
w
carried out up
u to the
screening and treatment. System
er 2011 in the fo
ollowing databas
ses: Medline (via
a OVID),
end of Octobe
Embase (via Embase.com), HTA
A and EED (via CRD NHS) and Psycinfo
P
(via OVID).
g various qualifierrs for “quality of life” were used as Subject
Searches using
heading or tex
xt word. See app
pendix 3.1 for an
n overview of the
e search
strategies and terms
t
used.
2.3.1.2.
Sellection criteria
Identified refere
ences were assesssed against pre--defined selection
n criteria
(in terms of pop
pulation, intervention, outcome and
d design –Table 2.5)
2
in a
two-step proced
dure: initial assesssment of the title
e, abstract and ke
eywords;
followed by full-text assessmen
nt of the selecte
ed references. When
W
no
a
and the
e citation was un
nclear or ambiguo
ous, the
abstract was available
citation was assessed based on
n keywords and fu
ull-text. Reference
e lists of
udies were scrutin
nized for additiona
al relevant citation
ns.
the selected stu
KCE Reportt 176
T
Table
2.5: Article selection criteriia
I
Inclusion
criteria
a
Exclus
sion criteria
P
Population
Screened or treatted
S
p
patients
for breast
c
cancer,
with a Caucasian
o
origin
and withoutt high
r
risk
factors
diseases, non
Other d
Caucasian, high risk wo
omen
In
ntervention
Any intervention relevant
A
r
t the Belgian setttings
to
Interve
entions not used in
n
Belgium
m
O
Outcome
Unique QoL weights
U
a
allowing
to derive QALYs
(
(=utilities)
Multi-d
dimension HRQoL
L
scoress, DALYs, HYEs, …
D
Design
Direct (TTO, PTO
D
O, SG)
o indirect (EQ-5D
or
D, SF6 HUI, QWB) va
6D,
aluation
m
methods
in primary
s
studies
Letterss, secondary studiies,
CUA w
with QALYs derive
ed
from th
he literature, …
Direct valuations using VAS
V
(not recommended in the
mic
KCE pharmaco-econom
guidelines)79.
QoL: Quality of Life. QALY: Quality adju
Q
usted life year. HRQ
QoL: Health-Related
d
Q
Quality
of Life. DALY
Y: Disability-Adjuste
ed Life-Years. HYE: healthy-yearse
equivalent;
TTO: Tim
me-Trade-Off. PTO:: Person Trade-Off. SG: Standard-Gam
mble.
H
HUI:
Health Utility In
ndex. QWB: Quality of Well Being scale
e. CUA: cost-utility
a
analysis.
VAS: visua
al analogue scale
KCE Report 176
6
2.3.1.3.
S
Screening
Breast Cancer
C
Sellection process
The flowchart of
o the selection p
process is presen
nted in appendix 3.2.
3
The
searches on th
he databases retu
urned 524 citation
ns. After exclusion
n of 172
duplicates, 352
2 unique citationss were left (see also
a
appendix 3.2
2). Hand
searching allow
wed us to identifyy 3 additional cita
ations. Two-hund
dred and
ninety (290) refferences were discarded based on title and abstract, leaving
65 references for
f full-text evaluation. Another 49 references
r
were excluded
e
at this stage, mostly
m
because off the unmet desig
gn and population criteria.
Overall, we sele
ected 16 primary sstudies (see appe
endix 3.2).
2.3.2.
Resullts
A summary of the
t selected studiies can be found in appendix 3.3. It
I should
be noted that this summary on
nly report metho
ods used to deriv
ve utility
w
not
values and their results. If other parameters were measured, they were
reported in the summary.
o utilities was don
ne according to the
e following stages
s:
The selection of
•
Determinattion of health state
es for which utilitie
es were needed
•
Selection of
o utilities
Selection of
o a basecase stud
dy
Selection of
o other studies
•
Pooling of selected utilities a
and calculation of percentage changes
2.3.2.1.
Dettermination of he
ealth states
Health states fo
or which utility valu
ues are needed are
a listed in Figure
e 2.1.
It should be no
oted that this fig
gure is a schema
atic representation
n of the
reflection proce
ess but not the model itself (de
escribed in section 3.2).
35
KCE Reports vo
ol
S
Screening
Breast Cancer
C
36
Figure 2.1: Hea
alth states for wh
hich utilities are needed (reflection process)
Before
e screening
Short term
m impact
of the sc reening
After scre
eening
(First year)
y
After screening
(Folllowing years)
Women ag
ged ≥ 70 years
Negative
e results
Women aged ≥ 70 years
Women aged ≥ 70 years
Positive results
False positive
p
Non me
etastatic
No
on metastatic
Breast canccer stage I
Breastt cancer stage I
Breast cance
er stage II
Breast cancer stage II
Breast cance
er stage III
Breast cancer stage III
Metasstatic
Metastatic
Breast cance
er stage IV
Breast cancer stage IV
True po
ositive
KCE Report 176
6
2.3.2.2.
S
Screening
Breast Cancer
C
Sellection of utilitiess
To select utility values, we first ttried to find Belgia
an data as recom
mmended
co-economic guid
delines of the KCE
E79. However, no Belgian
by the pharmac
data could be fo
ound.
Then, we tried to find the mosst complete study
y which best fit with
w
our
m was to avoid as much as possible the use of multiple
model. The aim
instruments and
d multiple popula
ations to derive them. Indeed, acco
ording to
the pharmaco-e
economic guidelin
nes of the KCE, it is strongly recom
mmended
to use the sam
me descriptive insstrument and the
e same set of va
alues for
quality of life we
eights coming from
m different studies
s79.
However, no sttudy assessing all of the heath sta
ates described in
n section
2.3.2.1 with the
e same design w
was found. We th
herefore tried to find the
study with the greatest
g
number o
of health states co
orresponding to ou
ur model
and to use it at the starting point of the selection process.
p
Selection of th
he base case study
We found only
y one study haviing assessed utility values for bo
oth nonmetastatic and metastatic patien
nts, i.e. the study of
o Lidgren et al80. We had
strument
the chance that this study alsso used the bettter available ins
he pharmaco-econ
nomic guidelines of the KCE, i.e. the EQaccording to th
5D79. This study
y was therefore th
he starting point of our selection pro
ocess.
80
Utility values in
i the study of Lidgren et al. were derived frrom two
methods, i.e. a direct valuatio
on method (i.e. the time-trade-offf (TTO)
S
patients and an indirect valuation
v
method using a
technique) by Swedish
generic instrum
ment (i.e. the E
EQ-5D instrumen
nt). Because pharmacoeconomic guide
elines of the KCE
E recommend the
e use of the EQ-5
5D, only
these valuations were retained (i.e. utility values from
f
EQ-5D and not from
ents and
TTO). In this sttudy, health statess were described by Swedish patie
valued using UK
K tariffs (because
e no tariffs from the Swedish popula
ation are
available). Hea
alth states descriptions can be fo
ound in Table 2.6
6. Utility
values for non-metastatic patients in the first year
y
(i.e. the yea
ar of the
ars as well as utility values for metastatic
treatment) and the following yea
scribed in Table 2
2.8.
patients are des
This study had the following limittations:
37
•
Utility values were measuring
g during out-patie
ent visits at a breast
b
cancer outpattient clinic (Karolinska University hospital), implying the
following limita
ations:
Utility values for
f non-metastatic
c patients did not fully take into account
the shortt term impact of surgery.
s
Howeverr, on an annual basis,
b
this shortt term impact was expected to co
over a limited leng
gth of
time and was therefore nott included in the m
model.
Utility values for metastatic patients
p
did not represent patien
nts in
hat these utility values
v
palliative care. It was therrefore assumed th
ected the quality of life of metasta
atic patients durin
ng the
only refle
first year of diagnosis.
The short term
m impact of diagn
nosis is also not ffully taken into account
(not meas
sured at the mom
ment of the diagno
osis), even if autho
ors of
this study
y reported that this
s impact was expected to be includ
ded in
the valua
ation (measured th
he year of diagnossis).
•
Non-metastattic patients were divided
d
in only tw
wo groups, i.e. the
e first
year of diagnosis and the follo
owing years. It w
was therefore assu
umed
emained constant. This
that after the year of treatment, utility values re
i supported by an US study where no significant
assumption is
difference in utility
u
values (from
m EQ-5D using U
US tariffs) was fou
und at
year 5, 10 and
d 1581. This US sttudy is described in the appendix 3.3.
•
It should also be noted that utility estimates for n
non metastatic pa
atients
ast cancer in the first year of diag
gnosis) and meta
astatic
(primary brea
patients werre similar (0.696 and 0.685 respectivelly). This
inconstistency
y may be due to th
he following reaso
ons:
Metastatic patients
p
only inc
clude patients going in out-patient
consultations (best cases).
Generic instru
uments such as the EQ-5D are lesss sensitive to ca
apture
relevant changes in healtth in a specific d
disease than dise
easei
How
wever, diease-spe
ecific instruments
s can
specific instruments.
only be used
u
if validated mapping
m
functionss to derive utilities
s from
these instruments are avaiilable, which was not the case79.
38
S
Screening
Breast Cancer
C
Table 2.6: Health states descriptions for the study of Lidgren et
e al.
Primary
b
breast
cancer (year 0-1)
Patients who had prima
ary diagnosis brreast of
within 1 year or le
ess prior to answe
ering the
cancer w
question
nnaire, no recurre
ence and no metastatic
disease
Recurrence (y
year 01)
Patients who had at least one recurrenc
ce (locoeral) within 1 year or less
regional and/or contra-late
prior to answering the questionnaire, and no
metastattic disease.
Primary
b
breast
cancer
and
recurrence
following yearrs
d
with a primary
Patients who had been diagnosed
ancer or their last recurrence more
e than 1
breast ca
year prio
or to answering th
he questionnaire,, and no
metastattic disease.
Metastatic patients
Patients who had metasta
atic disease
KCE Reportt 176
As showed in this
A
s table, the description include the following stage: being
in
nvited for screen
ning, having a brreast screen, waiiting for results, being
re
ecalled for furth
her examinations, having furthe
er examinations and
o
obtention
of a diagnosis, i.e. no
o evidence of brreast cancer. Fo
or the
a
assessment,
only three of the five EQ-5D
E
dimensions were used, i.e. usual
a
activity;
pain/disco
omfort; and anxietty/distress and it was assumed tha
at the
re
emaining two dimensions (i.e. mobility
m
and ability of self-care) were
u
unaffected.
The quality
q
of life effec
cts associated with true negatives
s and
fa
alse positives las
sted 12 months while true positivve and false neg
gative
w
were
measured for
f
the remaining life expectanccy. These values
s can
th
herefore not be used
u
to measure the
t short term im
mpact of screening
g. We
d
decided
to make th
he following assumptions:
•
True negativ
ve patients have
e utility values e
equal to the ge
eneral
population.
•
m impact of positive results at scre
eening is measure
ed by
The short term
the percentag
ge change betwee
en true negative and false positive.
Selection of otther studies
•
For other health states, we trried to find stud
dies having used
d similar
ation. The study of
o Lidgren et al.80 allowed
instruments for the same popula
ng utility values for the general Swedish
S
us to identify a study assessin
population strattified by age and gender using the same instrument (EQ-5D
with UK tariffs),, i.e. the study of Burström et al.82 These utility valu
ues were
therefore used for women aged 7
70 and over (see Table 2.8).
For the short term
t
impact of p
positive results affter screening, on
ne study
using the EQ-5
5D instrument wa
as identified (Gerard et al.)83. Th
his study
assessed utility
y values for false positive, true positive, false nega
ative and
true negative. Health
H
states were
e described by the UK population (and not
the Swedish po
opulation) but UK
K tariffs were used
d to valuate these health
states (as in the other selectted studies). A description
d
of the “false
s given in Table 2
2.7.
positive” state is
•
This impact is
s present until the diagnosis, i.e. on
n average 45 days
s after
screening acc
cording to IMA da
ata. After, either vvaluations of Burs
ström
et al.82 (generral population for false positive) orr valuations of Lid
dgren
et al.80 (non metastatic
m
or mettastatic disease yyear 1 for true po
ostive)
were used.
U
Utility
values for fa
alse positive and true
t
negative can be found in Table
e 2.8.
Itt should be noted that the study of Domeyer et al.84 described in app
pendix
3 assessed the short term impact of biopsy. How
3.3
wever, to avoid model
m
c
complexity
and be
ecause the biopsy
y is included in the
e description of a “false
p
positive”
in the stu
udy of Gerard et al.
a 83, we decided tto not take the stu
udy of
84
D
Domeyer
et al. in
nto account.
C
Concerning
the ev
volution of utility values for patientss with metastatic breast
b
c
cancer
in the long term, no study wa
as found.
KCE Report 176
6
S
Screening
Breast Cancer
C
39
Table 2.7: Description of a “fallse positive” statte (Gerard et al)83
•
S
She is invited by letter for routine breast
b
screening.
•
T
The appointment is about 2 weeks from receiving the
e invitation.
•
T
The visit at the bre
east screening ce
entre takes about half an hour, whic
ch may include wa
aiting time.
•
A female radiogra
apher asks about any
a symptoms or history of breast disease and expla
ains what will hap
ppen.
•
T
To take the X-ray
y she is asked to undress to the waist.
w
Each breast is placed in turn
n between two sp
pecial X-ray plates
s and
ccompressed to ge
et the best possiblle picture.
•
S
She is asked by le
etter to go to the breast
b
screening centre
c
the followin
ng week.
•
O
Other tests are ne
eeded because the breast X-ray res
sult is not clear.
•
T
This visit may take
e up to half a day.
•
T
The breast X-ray is repeated.
•
T
The doctor examines her breasts.
•
T
The doctor may carry out an ultraso
ound examination
n.
•
F
Fluid from the affe
ected area is take
en for laboratory analysis
a
using a fin
ne needle to do th
his her breast mayy again be compre
essed
b
between the X-ray
y plates.
The results of the tests
are ready within the
week
•
T
The tests show no
o evidence of brea
ast cancer.
Quality of life effects
e
of
routine
breast
ort term)
screening (sho
QoL of some wom
men is affected by
y the experience of routine breast screening and brreast cancer diagnosis. The effects
s may
The Q
continue for some time
e.
Receiving
invitation
•
M
Most women are pleased to receive
e the invitation.
•
S
Some women are
e made nervous, anxious
a
or depressed, and are worrried about having breast cancer.
•
M
Most women carry
y on with their usu
ual activities and interests.
i
•
S
Some women are
e anxious and dep
pressed, unable to
o concentrate, sleep badly and are moody and irritab
ble. They are unable to
ccarry on with theirr usual activities and
a interests.
•
P
Personal and sexual relationships may
m be affected.
Routine breastt screen
Further tests
the
Waiting for th
he day of
the appointme
ent
40
S
Screening
Breast Cancer
C
At the breast screening
s
clinic
Waiting for the
e results
KCE Reportt 176
•
M
Most women are nervous, but are not
n anxious or dep
pressed.
•
M
Most women are not embarrassed by the screening procedure.
•
M
Most women are not unduly worried
d about breast ca
ancer developing.
•
M
Most women find the breast X-ray is
i uncomfortable and
a slightly painfu
ul, but this is shortt lived.
•
S
Some women find
d the breast X-ray
y very uncomfortab
ble and painful.
•
M
Most women carry
y on with their usu
ual activities and interests.
i
•
S
Some women are
e anxious and dep
pressed, un-able to concentrate, sleep badly and arre moody and irrittable. They are unable
tto carry on with th
heir usual activities
s and interests.
•
P
Personal and sexual relationships of
o some women may
m be affected.
If reccalled for further te
ests:
Clear results after the
test
•
M
Most women are very
v
anxious at be
eing recalled for further tests.
•
O
One of the tests, where
w
the doctor removes fluid from
m the affected are
ea, is painful.
•
M
Most women are reassured by the clear results.
•
S
Some women rem
main anxious for up
u to a year before
e they are back to
o their usual self.
Table 2.8: Description of the se
elected utilities
Author (year)
Instrument
P
Population for he
ealth state
d
description
Lidgren et al.
(2007)80
EQ-5D
S
Sweden patients
((Mean age: see health states)
Burström et
al. (2001)82
EQ-5D
Gerard et al.
(1999)83
EQ-5D
Po
opulation for valu
uation
Hea
alth state
Mean
valu
ue
UK
K tariffs (general population)
p
Prim
mary breast cance
er (Year 0-1); Mea
an age: 56
0.696
UK
K tariffs (general population)
p
Brea
ast cancer (follow
wing years); Mean age: 58
0.779
UK
K tariffs (general population)
p
Meta
astatic patients; Mean
M
age 56
0.685
Wom
men aged 50-59
0.833
Wom
men aged 70-79
0.792
Wom
men aged 80-88
0.740
True
e negative
0.940
S
Sweden patients
((Mean age: see health states)
UK
K tariffs (general population)
p
W
Women from UK aged
a
40-64
yyears (eligible for screening)
K tariffs (general population)
p
UK
KCE Report 176
6
2.3.2.3.
S
Screening
Breast Cancer
C
Poo
oling of selected
d studies and callculation of percentage
cha
anges
A summary of selected utilities and of calculation of percentage changes
c
n Figure 2.2. The
e utility values of the study of Burs
ström et
can be found in
al.82 were chosen as the initial values of the mode
el (first state of th
he model
ding to women ag
ge. Then, the perrcentage
(A)). These values varied accord
e to these valuess was applied. It was assumed that these
change relative
percentage cha
anges did not varyy according to the women age (no data).
d
hort term impact of the screening
The next stage
e concerns the sh
g. It was
assumed that utility
u
values for ttrue negative wom
men were equal to utility
values in the general
g
populatio
on (A). Then, the percentage decrrease in
utilities betwee
en true negative women and false positive wom
men was
calculated, i.e. -16% (B). Initia
al values were thus
t
maintained for true
en and decreased
d by 16% for wom
men with a positiv
ve result
negative wome
after screening (false or true possitive). As mention
ned in the section 0, these
m
for 45 days.
utilities will be maintained
41
For the first year of screening, wo
F
omen without bre
east cancer had utility
v
values
equal to th
he general popula
ation (A). For true
e positive, utility values
v
o the study of Lid
of
dgren et al. were used.80 To make
e the link betwee
en the
s
study
of Lidgren et al.80 and the study of Burström
m et al.82, percentage
c
changes
between values for the sa
ame population w
were used, i.e. Sw
wedish
w
women
aged 50-5
59 (and UK tariffs
s). Utility values w
were therefore red
duced
b 16% ((0.696-0..833)/0.833) for non
by
n metastatic pa
atients (C) and by
y 18%
((0.685-0.833)/0.833) for metastatic
c patients (E).
F the next yearrs, people from the
For
t
general popu
ulation who developed
n
non-metastatic
or metastatic breas
st cancer had utility values reduce
ed by
16% (C) and 18%
% (E) respectively
y (as calculated a
above). Non-meta
astatic
p
patients
who stay
yed in this stag
ge had their utiliity decreased by
y 6%
c
compared
to the general
g
population ((0.779-0.833)/0
0.833) and maintained
th
he years after (D
D). Metastatic patients maintained their utility until death
d
(G).
42
S
Screening
Breast Cancer
C
KCE Reportt 176
Figure 2.2: Perrcentage change
e in utilities
Before
e screening
Short term
m impact of the
screeniing (45 days)
After screening
A
(First year)
After screeniing
(Following yea
ars)
Women age
ed = 70 years
True negative
Wome
en aged = 70 years
Women aged = 7
70 years
A
A
A
A
N metastatic
Non
Non metasta
atic
Brea
ast cancer stage I
Breast cancer sstage I
Brea
ast cancer stage III
Breast cancer sttage II
Brea
ast cancer stage III
Breast cancer sttage III
Positive
P
results
False positive
True positive
B
C
C
D
Metastatic
Brea
ast cancer stage IV
V
F
E
Metastaticc
Breast cancer sttage IV
F
G
KCE Report 176
6
2.3.3.
S
Screening
Breast Cancer
C
Discu
ussion
To include the quality of life im
mpact of screenin
ng in the analysiis, utility
h health state of tthe model had to be identified. The
e aim of
values for each
this chapter wa
as therefore to select these values. The method wa
as based
on the KCE pha
armaco-economicc guidelines79. We
e tried to avoid the use of
multiple instrum
ments and multiple valuations and focused on utility
y values
derived from the
e EQ-5D instrume
ent.
•
The analys
sis had the following limitations:
•
No Belgian
n data were availa
able and a transfferability analysis was not
possible (n
no access to prim
mary data). Even ifi we expected th
hat using
UK tariffs instead of Belgia
an valuations wo
ould not greatly in
nfluence
be interesting for future models.
results, Belgian data would b
•
t
impact of su
urgery and of diag
gnosis was not ta
aken into
The short term
account be
ecause no valid da
ata were available
e.
•
Even if the
e EQ-5D is one o
of the best availa
able instrument to
o assess
these utilitiies (according to the KCE pharma
aco-economic guid
delines),
this instrum
ment is less sen
nsitive than disea
ase specific instrruments.
Consequen
ntly, it can be exp
pected that the im
mpact of some co
onditions
such as a mastectomy (p
partial or total) would have bee
en more
important if a disease sp
pecific instrumen
nt instead of a generic
nsitivity could exp
plain the
instrument had been used. This lack of sen
ntage change be
etween patients with breast cancer and
low percen
women in the general pop
pulation or between metastatic and
a
non
q
of life from disease
metastatic patients. The asssessment of the quality
struments was ne
evertheless not investigated in this chapter
specific ins
because th
hese instruments d
do not permit to derive QALYs.
•
Finally, the
e review of the literature showed
d an important variability
v
between re
eported utility estimates for breast cancer health sta
ates (see
appendix 3.3),
3
revealing a high level of uncertainty
u
aroun
nd these
parameters
s. Because of th
his uncertainty, a sensitivity analysis on
these parameters should be
e done in the chap
pter on model resu
ults.
43
3 DECISIO
3.
ON ANALY
YSIS
To quantify whatt the implications
T
s of our findingss are on the Be
elgian
s
situation
we cons
structed a decisio
on analysis model using two diffferent
a
approaches.
For the first simple approach, we ap
pplied data from IMA,
c
cancer
registry an
nd data from the literature
l
on the B
Belgian life tables
s (see
b
below).
For the se
econd, we constrructed a simple ttime dependent cohort
c
w annual cycles
with
s.
W consider perfo
We
orming one Belgia
an decision analyysis a better apprroach
th
han trying to ada
apt the models discussed
d
in cha
apter 2 to the Be
elgian
s
situation.
Indeed, Belgian data nee
eded to paramete
erize these modells are
n available and
not
d we would merely reproduce tthe already published
fiindings of these models,
m
as we wo
ould be obliged to
o use the same (m
mainly
U data.
US)
W look at the effe
We
ect of introducing mammography sscreening in addition to
th
he currently existing situation with the opportunistic screening going on at
th
he current level. This
T
has the adva
antage that we ca
an use Belgian da
ata as
b
baseline
without having
h
to modify then, as this can only be done making
u of an addition
use
nal number of no
on verifiable assu
umptions. We des
scribe
h
here:
•
a used in this deciision analysis;
Available data
•
Additional lite
erature review foc
cused on qualityy of life related to the
screening and
d to the breast can
ncer as such;
•
The model us
sed for this decisio
on analysis.
44
S
Screening
Breast Cancer
C
3.1. Data so
ources
Belgian life tab
ble (2009)
Overall surviva
al was taken fro
om the Belgian life table of 200
09 from
be.STAT (http:///statbel.fgov.be)
Belgian Cance
er Registry (BCR
R)
The Belgian Cancer
C
Registry F
Foundation is an
n public institution which
collects data concerning
c
new ccancer cases in Belgium and ma
akes up
statistics from these data (http://w
www.kankerregistter.org/).
Belgian organized screening
As recommend
ded by European Commission, Be
elgium started a national
organized scree
ening programme
e. The target age groups as defined by the
program are wo
omen aged 50 to 69 years. Belgian
n breast cancer sc
creening
programs
a
are
organized
d
by:
Brrumammo
(Bruxelles,
http://www.brum
mammo.be/), Cen
ntre Communauta
aire de Référence
e pour le
dépistage des
s cancers (CCR
Ref: http://www.c
ccref.org/) (Comm
munauté
Française) and
d BorstKankerOp
psporing (BKO) (Vlaamse
(
Gemee
enschap:
http://www.zorg
g-en-gezondheid.b
be/).
Intermutualistiic Agency (IMA)
The Intermutua
alistic Agency (IMA
A) centralises data coming from all Belgian
sickness funds
s. IMA compiled and published several reports on the
national screen
ning program con
ntaining data on the
t
target age grroups as
defined by the
e program (50-6
69 years). IMA complemented this with
information on persons outside
e the target age-group, with a particular
p
t
used, delayys between scree
ening tests and possible
focus on the tests
confirmation an
nd treatments follo
owing testing (http
p://www.nic-ima.be
e/).
Dutch Nation
nal Evaluation Team for Bre
east cancer sc
creening
(DNETB)85.
The Dutch National Evaluatio
on Team for Breast
B
cancer sc
creening
eport with their findings covering
g the period 1990-2007
published a re
containing inforrmation on age sspecific stage disttributions in the screened
s
population.
KCE Reportt 176
SEER database
S
T Surveillance, Epidemiology, an
The
nd End Results (S
SEER) Program of
o the
N
National
Cancer In
nstitute works to provide informatio
on on cancer stattistics
in
n an effort to red
duce the burden of cancer among the U.S. Population
(http://seer.cancerr.gov/). SEER colllects data on canccer cases from va
arious
lo
ocations and sourrces throughout th
he United States. Data collection began
b
in
n 1973. As they used an outdated distribution we could not incorp
porate
th
hese in the model.
3
3.2.
Model de
escription
In
n a first simple approach
a
we app
plied the 22% redu
uction in breast ca
ancer
m
mortality
caused by
b screening com
ming from RCT and its range, res
sulting
frrom the results of
o the meta-anallysis of Gøtzsche
e et al, 20084 on the
B
Belgian
life table. We assume here
e that the reductio
on in women age
ed 707 is similar to the
74
t
reduction in other age group
ps. We also ass
sume,
fo
ollowing Barratt et
e al 200536 that benefit accrues linearly to a ma
aximal
le
evel over first five
e years after startting screening and that benefit dec
clines
linearly to nothing
g over five years
s after stopping screening. Life years
s
saved
can then be derived from th
he life table. How
wever, effects of harms
h
a effects on qua
and
ality of life resultin
ng from earlier dia
agnosis, over-diag
gnosis
a stage-shift is more difficult to assess
and
a
in this ap
pproach. Therefore
e this
a
approach
was onlly used for cross validation by com
mparing it with a more
c
complex
approach
h that makes use of
o the stage-shift caused by screen
ning.
T
The
second apprroach makes use
e of the Belgian C
Cancer Registry (BCR)
d
data
on incidence
e of invasive canc
cer and DCIS forr the construction
n of a
tiime dependent state transition cohort model with annual cycles.
T model compares 2 cohorts:
The
•
A cohort of women
w
starting at age 70 where screening is extend
ded to
the population
n in the age group 70-74, where a part of the wo
omen
participates in
n the screening an
nd where a part o
of the cancers is found
f
by screening,, depending on participation
p
rate and sensitivity of
o the
screening. Th
here is a mix of sc
creen detected an
nd not screen detected
cases (interva
al cancers and cancers
c
amongstt unscreend wom
mens).
The screen detected
d
cancers will have a diffe
erent stage distrib
bution
than the cancers not detected by
b screening.
KCE Report 176
6
S
Screening
Breast Cancer
C
•
A cohort of
o women starting at age 70 whe
ere the screening is not
extended beyond
b
the age off 69 years. For th
his cohort all wom
men have
the stage distribution
d
of the non screened.
All women are followed to death
h. The cumulative number of life ye
ears, the
horts are
number of QALYs and deaths to breast cancer of the two coh
erall mortality is no
ot compared as in
n the end everybod
dy dies.
compared. Ove
We assume tha
at:
•
Survival an
nd quality of life of the women depe
ends only on the stage of
the tumor at the moment tthe tumor is dete
ected and the age of the
nd not on the pressence or absence of screening;
women, an
•
All benefit of the screening rresults from the stage-shift, the diffferences
stribution caused by the screening..
in stage-dis
Harm caused by false positivves at the mome
ent of the scree
ening is
s
by asssuming 3 screening rounds with a 2 years
accounted for separately,
interval in the
e participation women and apply
ying recall rates
s at the
proportion wom
men that are alive and without brea
ast cancer at the moment
the screening ro
ound actually take
es place.
Figure 3.1 show
ws the different ccompartments in the two cohorts and the
transitions betw
ween them.
In the unscreen
ned cohort, transiitions between co
ompartments from
m year to
year are determ
mined by:
•
Incidence of
o breast cancer;
•
Stage distrribution of unscree
ened cancers;
•
Stage spec
cific survival; and
•
Age specific overall mortalityy due to other cau
uses.
On top of that, for
f the cohort whe
ere screening take
es place, transition is also
determined by some
s
aspects of tthe screening:
•
Lead time as
a part of the cancers will be found
d earlier;
•
The propo
ortion of cancers found by scree
ening and proporrtion not
found by sc
creening and their respective stage
e distributions.
45
As survival and quality of life depends on both age and time since
A
d
diagnosis
in the model,
m
a separate
e compartment is made for each age
a of
d
diagnosis
and stage, and stage specific survivall is than applied
d. As
s
screening
is applie
ed during 5 years and there is an a
assumed lead time
e of 2
y
years
(or 3 in sen
nsitivity analysis) the number of co
ompartments remained
m
manageable.
T
Transitions
betwee
en stages are nott included as stage
es are assessed at
a the
m
moment
the diagn
nosis is made folllowed by treatme
ent. Even if the ca
ancer
e
evolves
after trea
atment it does no
ot necessarily go through the 4 stages
a
anymore.
46
S
Screening
Breast Cancer
C
KCE Reportt 176
Figure 3.1: Comparison of the two cohorts with
h and without a screening
s
progra
am
IInvasive cancer d
detected by
screeniing
Healthy women
iinterval cancer in s
screened women
Invasive cancer in unscreened womeen
Cohorrt with screeening
I
II
III
IV
I
II
III
IV
All ccause deaths
I
II
III
IV
DCIS
Co
ohort
w
without screeening
Invasive cancer in unscreened womeen
Healthy women
I
II
III
IV
DCIS
All ccause deaths
KCE Report 176
6
S
Screening
Breast Cancer
C
Figure 3.2: Compartments in th
he two cohorts and
a the transition
ns between them
m
DCIS &
over‐
d
diagnosed Breast
cancer stage I Breast
cancer stage II
Healthy women
Death
Breast
cancer stage III
Breast
cancer stage IV
47
48
S
Screening
Breast Cancer
C
3.3. Descrip
ption of the parrameters
3.3.1.
Age specific
s
overall survival
Overall surviva
al was taken fro
om the Belgian life table of 200
09 from
be.STAT (http:///statbel.fgov.be) after adjusting fo
or breast cancer specific
mortality based on data from the Belgian Cancer register.
r
3.3.2.
Breas
st cancer inciden
nce
For the baseline
e without screenin
ng the BCR data on
o incidence of DCIS
D
and
the 4 stages for invasive for the age group 70-74
4 of the period 2004-2008
ere is some opporrtunistic screening
g in that age grou
up. From
were used. The
the IMA data we
w infer that in Flanders the cov
verage with at le
east one
mammography in the past 2 yea
ars is 18% (for de
etails see the KC
CE report
ps)2. Given that we can
172 on breastt cancer screening in risk group
assume that an
n important part o
of this is also for diagnostic
d
and follows up
purposes, so we
w choose to use
e data issued from
m Flanders becau
use they
are less contam
minated by opportu
unistic screening.
For the situatio
on where screen
ning takes place,, incidence in the 70-74
group will increa
ase with a numbe
er of cancers coming from two sourrces:
•
Lead time, cancers that would have appeare
ed later but are fou
und now
o lead time. This will lead to a co
ompensatory decrease in
because of
number of cases in the folllowing years. The
e moment and de
egree of
d
on the a
assumed lead tim
me (see point 3.2
2.2). We
this shift depends
used 2 yea
ars lead time in tthe baseline and 3 years in the se
ensitivity
analysis.
•
gnosis invasive cancer, we mod
deled the over diagnosis
Over diag
based on the findings in th
he literature as described
d
in the literature
ove under 2.1.3.5.. We assume a ra
ange of 2 to 30% for over
review abo
diagnosis excluding
e
DCIS.
•
Over diag
gnosis DCIS, we
e model the overr diagnosis of DC
CIS in a
different way:
w
we use the o
observation that in Flanders the in
ncidence
DCIS per 100
1 000 is twice in the group 60-6
69 where screenin
ng takes
place com
mpared to the age
e-groups 70-74 and
a
75-79 where
e only a
limited am
mount of opportunistic screening takes place. Th
his is in
contrast with the Brussels ca
apital region and Walloon
W
region where
w
the
CIS is much less pronounced. So we
e take as an estim
mation of
drop in DC
KCE Reportt 176
over diagnosis the difference in
i DCIS incidence
e in Flanders bettween
ps 60-69 and 70--74, augmented b
by 1.5 to adjust fo
or the
the age-group
fact that scree
ening coverage is only 60% as a prroxy for overdiagn
nosed
DCIS. This brrings us to an ove
er diagnosis of DC
CIS of 40 per 100
0 000
women per ye
ear.
3
3.3.3.
Participa
ation rate
W used a 70% pa
We
articipation (plaus
sible range 60% to
o 80%) as baselin
ne.
3
3.3.4.
Proportio
on of screen dettected breast ca
ancers
The data of the Be
T
elgian screening program
p
show tha
at in the age grou
up 506 49% of the cas
69,
ses are found by screening, and th
he rest is either interval
c
cancer
or not partticipating in the sc
creening. Among the screened wo
omen,
7
75%
of the found cancers are scree
en-detected and 2
25% is interval ca
ancer.
W used a proporrtion of cancers fo
We
ound among the w
women participating in
s
screening
of 70% (plausible range 60%
6
to 80%).
3
3.3.5.
Recall ra
ate
We assume a rec
W
call rate of 3.5%
% based on the d
data from the Fle
emish
s
screening
program
m concerning follo
ow up rounds (ass the screening would
w
b an extension of the screening
be
g among women aged 50-69. Fo
or the
s
sensitivity
analysis
s we used 2% in an
a optimistic scen
nario and 5 and 10
0% in
th
he more pessimistic scenario (10% recall rates are observed fo
or the
m
moment
in certain regions).
A a baseline we assume a delay of 45 days, base
As
ed on IMA data, with
w a
p
plausible
range fo
or the sensitivity analysis
a
of 36 and
d 45 days (subtra
acting
a adding 20%).
and
T short term im
The
mpact of positive results
r
at screeniing were measure
ed by
th
he percentage ch
hange in utility va
alues between trrue negative and false
p
positive
results.
KCE Report 176
6
3.3.6.
S
Screening
Breast Cancer
C
Stage
e distribution and
d stage shift
We take estima
ations of the stag
ge distribution for breast cancer amongst
a
screened and unscreened
u
from the BCR data on
o the Flanders and
a
data
provided by the
e Flemish screenin
ng program.
For the stage distribution
d
in the unscreened wom
men, we can cons
sider the
stage distributio
on amongst wom
men in the group 70-74
7
in Flanders
s for the
years 2004 - 2008 a good esstimation. The stage shift will be
e slightly
d as there is som
me opportunistic screening in tha
at group
underestimated
going on, see above.
a
For stage distribution in the scre
eened population, the base case es
stimation
e data from the D
Dutch National Ev
valuation Team fo
or Breast
is based on the
cancer screenin
ng report of 2009
9 (DNETB)85 who
o provide data spe
ecifically
for the age group
g
70-74 from 1998-2007. Although
A
using 2 stage
distributions fro
om different sourrces is a subopttimal way of mod
deling a
stage shift we think
t
this approxim
mates best the Be
elgian situation, as
a we do
not have date on screen detectted cancer in this
s age group. We assume
on of cases amon
ng the non screen
ned and interval cancer
c
to
stage distributio
be the same, ba
ased on the data from the Flemish screening program.
The Flemish screening
s
program provided data
a on the stages among
screen detecte
ed cancers, interrval cancers and
d cancers amongst non
participants, co
ollected amongstt women who ga
ave their consen
nt in the
period 2001-2006. Stage distribu
ution of interval ca
ancers and cancer among
s is very similar.
non participants
49
Table 3.1: Stage distribution amo
T
ong screen dete
ected breast can
ncers,
in
nterval cancers and cancers among
a
non partticipants, age 50-69,
5
F
Flemish
screenin
ng program 2001-2006.
Screen
n
cancerrs
detected
In
nterval cancers
Cancers amongst
non participan
nts
S
Stage
n
%
n
%
n
%
I
2586
62.5%
62
24
41.5%
1454
41.8%
%
III
1306
31.6%
65
56
43.6%
1460
42.0%
%
IIII
232
5.6%
20
00
13.3%
493
14.2%
%
IV
V
15
0.4%
24
4
1.6%
71
2.0%
%
T
TOTAL
4139
100%
15
504
100%
3478
100%
%
T
This
baseline stag
ge shift we call Sce
enario 1:
Stage distribution
S
n of
c
cancers
not foun
nd by
s
screening
B
BCR
data (Flemis
sh
p
population,70-74y
y, 20042
2008)
S
Stage %
% I II III IV 31.6
6% 42.3
3% 16.6
6% 9.5
5% Sta
age distribution of
o
can
ncers found by
scrreening
Da
ata of the DNETB
B
scrreening report 20
009
Sttage % I II III IV 80%
% 18.7% 0.8%
% 0.5%
% 50
S
Screening
Breast Cancer
C
Important rem
mark: It is importtant to note that this shift concerrns only
screen detecte
ed cancers and that in the cohort with screening interval
cancers and nonparticipants
n
ke
eep the stage distribution of can
ncer not
found by screening. In most casses this is around 50% but depends on the
er values of the sccreening and varie
es in time.
other paramete
For the sensitiv
vity analysis we usse 2 supplementary scenario’s:
As the stage distribution
d
from the Dutch National Evaluation Team
T
for
Breast cancer screening
s
report o
of 2009 may be more
m
favorable th
han what
can be achieved in the Belgian ccontext, we used as
a an alternative scenario
s
bution for screen detected patients
s of the age grou
up 50-69
the stage-distrib
from the Flemis
sh cancer screenin
ng program.
This we call Sce
enario 2:
Stage distributtion of
cancers not fo
ound by
screening
BCR data (Flem
mish
population,70--74 years,
2004-2008)
Stage distribu
ution of
cancers found
d by
screening (Fle
emish
screening pro
ogramme
(50-69 years)
Stage % Stage
% I II III IV 31.6% 3
4
42.3% 1
16.6% 9.5% I II III IV 62
2.5% 31
1.6% 5
5.6% 0
0.4% In a third scena
ario we use a sligh
htly different mode
eling approach.
Instead of usin
ng stage distributtions amongst sc
creened and uns
screened
women, we ass
sume that introducing screening in the group 69-74 will shift
the stage distrib
bution amongst alll breast cancer cases
c
in the popu
ulation to
the stage distribution of the wom
men 60-69 in the same period, using data
om the Belgian bre
east cancer registtry.
for Flanders fro
KCE Reportt 176
T
This
we call scena
ario 3
Stage distribution
S
n of
c
cancers
not foun
nd by
s
screening
B
BCR
data (Flemis
sh
p
population,70-74
years,
2
2004-2008)
Sta
age distribution
am
mongst all breast
can
ncers if screenin
ng
lev
vels are similar to
o
lev
vels among 60-69
9 in
Fla
anders
S
Stage %
Staage
% I II III IV 31.6
6% 42.3
3% 16.6
6% 9.5%
% II II IIII IV
V 45.7% 35.9% 12.5% 5.9% 3
3.3.7.
Stage sp
pecific relative survival
Stage specific su
S
urvival was taken
n from Belgian stage specific annual
s
survival
data (take
en from KCE repo
ort 150A)86. We o
only have data up
p to 5
y
years.
We used data from the Dutch
D
cancer reg
gister taken from
m the
w
website
(http://ww
ww.cijfersoverkank
ker.nl) to supplem
ment until 7 years
s (see
a
appendix
4.1). We
e assumed that survival conditiona
al on stage is similar in
s
screened
and uns
screened breast cancer
c
patients. A
As a sensitivity ana
alysis
w used also:
we
•
d
for women above 70 years
s per
Entirely the Dutch survival data
T relative surviv
val curve shows a lower relative su
urvival
stagegroup. The
for women above 70 compared with the overrall survival. This
s may
ct that older wome
en support the invvasive treatments
s less
reflect the fac
well but it is also
a
possible thatt there is undertre
eatment of the elderly.
Moreover, the
e data include pa
atients that were treated more tha
an 20
years ago, this may also explaiin the lower relativve survival.
•
val data coming
g from breast cancer research
h UK
British surviv
(http://info.can
ncerresearchuk.orrg/) They provide 10 years survival data
but survival is
s considerably low
wer than the Dutch
h or Belgian data. One
of the problem
ms with 10 year survival data is tthe fact that it re
eflects
survival of persons treated at
a least 11 yearss ago, given the
e fast
evolution in brreast cancer treattment this is a long time.
KCE Report 176
6
S
Screening
Breast Cancer
C
•
urvival data supplemented by Fren
nch 10 year survival data
Belgian su
coming fro
om87. The probllem of the evo
olution in breast cancer
treatment apply
a
here as for tthe British data.
We did not use
e US SEER data as they use an outdated
o
staging method,
so that survivall curves per stage
e are not comparrable to the other sources
and difficult to incorporate in the model.
The survival curves can be found
d in the annex.
3.3.8.
•
In the study of
o Lidgren et al.80, non-metastatic p
patients were divid
ded in
only two groups, i.e. the first ye
ear of diagnosis a
and the following years.
y
atients in stage I, II, III (groupe
ed as non meta
astatic
Therefore pa
patients) were
e assumed to have the same utility. This assumption is
supported by the fact that for years
y
2001-2006, the treatment wa
as the
ort on
same for patients in stage I, II, III according to the KCE repo
ncer86. Note that more recent data
a may
quality indicattors in breast can
change this picture because many cancer found
d by screening are
e now
onservative surge
ery. Neverthelesss, data to prove
e this
treated by co
assumption are
a not available and we found no
o study comparing the
impact of partial
p
versus to
otal mastectomyy on quality off life
corresponding
g to our inclusion criteria.
•
Utility values for
f non-metastatic
c patients (after th
he year of surgery
y) and
metastatic pa
atients were assu
umed to remain cconstant across years.
y
For non-meta
astatic patients, th
his assumption iss supported by an US
study showin
ng no significant differences at yyear 5, 10, and 1581.
Nevertheless,, as a sensitivity analysis we applyy a 20% decreme
ent in
QALYs for tak
king into account a variation of utilitty values across years.
y
QALY
Y
Number of life years was calcullated for each sta
age and a stage and this
or the quality of llife (QALYs), bas
sed on a literature
e search
was adjusted fo
(see point 2.3).
We made some
e assumptions:
•
Utility value
es at start of the m
model (before scrreening) were stra
atified by
age but percentage changess relative to these
e values were ass
sumed to
ccording to the ag
ge of the women (we did not have data on
not vary ac
this). For the sensitivity a
analysis, we app
ply a 20% reduction or
increase.
•
w negative results had utility values equal to the general
Patients with
population..
•
In the asse
essment of utility values for true ne
egative and false positive
results, mo
obility and ability o
of self-care were assumed
a
to be un
naffected
by screenin
ng.
51
•
At baseline, we
w did not discou
unt QALYs. For th
he sensitivity ana
alysis,
discount rates
s of 1.5%, 3% and
d 5% were applied
d.
P
Parameters
used in
i the model are shown
s
in table 3.2
2.
52
S
Screening
Breast Cancer
C
KCE Reportt 176
Table 3.2: Para
ameters used in the model
Parame
eters
No screenin
ng
Base case
c
Sensitivity ana
alysis
3.3.1
Age spe
ecific overall survivval
Belgian life-table
Belgian
n life-table
Belgian life-tablle
3.3.2
Breast cancer
c
incidence
BCR data
(Flanders
population, 20042008)
BCR data (Flemish
ation, 2004-2008)
popula
increas
sed by lead time.
over-diiagnosis
invasiv
ve cancer of
DCIS
BCR data (Flem
mish population, 2004-2008)
2
increased by lea
ad time. over-diag
gnosis invasive
cancer of DCIS
Lead tim
me
2 years
s
3 years
Over-dia
agnosis invasive
cancer
10.0%
range from 3 to 30%
Over-dia
agnosis DCIS
40/100
0 000 women per
year
40/100 000 wom
men per year
3.3.3
Participa
ation rate
70.0%
range from 60%
% to 80%
3.3.4
Proportiion of screened
detected
d cancers
70.0%
range from 60%
% to 80%
3.3.5
Recall rate
3.5% (Flemish
ning program)
screen
range from 2% to 10%
Duration
n of period after
positive result
45 day
ys
range from 36 to
t 54 days
QALYs lost in this period
16.0%
estimated between 13% to 19%
3.3.6
Scenario 2
Scenario 3
Stage distribution
BCR data (F
Flemish
population, 7074years, 20042008)
Data of the DNETB
ning report 2009
screen
Stage distributio
on of
Flemish screening
0-69)
programme (50
ge distribution of
Stag
BCR
R (Flemish women
n
60-6
69 (screened and
not screened)
Stage I
31.6%
80.0%
62.5%
45.7
7%
Stage II
42.3%
18.7%
31.6%
35.9
9%
KCE Report 176
6
S
Screening
Breast Cancer
C
53
Stage III
16.6%
0.8%
5.6%
12.5
5%
Stage IV
V
9.5%
0.5%
0.4%
5.9%
%
3.3.7
Stage specific relative
survival
Belgian stag
ge
specific ann
nual
survival data
a
supplemented until
D
7 years by Dutch
data
Belgian
n stage specific
annuall survival data
supplemented until 7
b Dutch data
years by
Dutch survival or
o British survival or Belgian/French
h
survival
3.3.8
QALY
Stage II III IV
-constant
- consttant
-20.0%
Stage III IV
-constant
-consta
ant
-20.0%
Stage IV
V
-constant
-consta
ant
-20.0%
Age rela
ated QALY
-constant
-consta
ant
range from + 20
0% to -20%
Discoun
nted QALY
discounting rate
e + 1.5%. 3% and 5%
54
S
Screening
Breast Cancer
C
3.4. Results
s
In the baseline scenario the mod
del predicts that th
here would be 130
07 years
er 100 000 (13,1 p
per 1000) women invited for screen
ning and
of life saved pe
395 per 100 00
00 (3.9 per 1000) QALYs. The mod
del also predicts that 128
deaths would be
b averted per 100 000 women screened
s
(1.3 pe
er 1000),
being a reductio
on of 21% (numbe
er needed to be offered
o
screening: 782).
Because of the
e considerable un
ncertainty surroun
nding the parametters and
model structure
e we did an exten
nsive sensitivity analysis.
a
Most unc
certainty
is not due to ra
andom error but d
due to issues rela
ating to the right choice
c
of
source of inforrmation on the p
parameter. We did not do a prob
babilistic
sensitivity ana
alysis, as it wa
as not possible to choose app
propriate
probability-distrributions in a meaningful way.
Table 3.4 show
ws the results of th
he sensitivity analysis, the plausible
e ranges
used for this an
nalysis was discu
ussed in 3.3, desc
cription of the parrameters
and justification
n of chosen valuess.
The number off years of life gain
ned remains fairly
y constant under different
T number of QA
ALY gained or lostt varies much more under
assumptions. The
different assum
mptions. This is partly due to th
he fact the a lott of the
uncertain or va
ariable parameters have an impa
act on the quality of life
gained rather th
han on mortality, such as high rec
call rates, over dia
agnosis,
apart from the values
v
accorded tto the QALYs.
Assumed degre
ee of over-diagno
osis has a strong impact on QALYs
s gained
and under the higher assumed
d values of 20% or 30% even im
mply that
b lost instead o
of gained. Years of life gained in
ncreases
QALY would be
slightly, this due
e to the fact that an over diagnose
ed case cannot be
ecome a
new case in the
e model, one could argue that this is
i somewhat of an
n artifact
but the effect is
s very small.
Recall rates of 10% also can sh
hift the balance to
owards a loss of QALYs.
ecall rates are actu
ually found in som
me parts of Belgium
m.
Ten per cent re
Assumptions on
n the choice of th
he appropriate surrvival curve have both an
impact on years of life gained and QALYs gained. The Dutch and the
e number of life years
y
gained but lead to a
British survival data increase the
val data suppleme
ented by
loss of QALYs in certain scenarios. Belgian surviv
where in between.
French 10 yearr survival is somew
KCE Reportt 176
In
ncreasing the ass
sumed lead time to
t 3 years has an
n impact on both years
of life gained and QALYs.
o
Q
T model’s estim
The
mation of the numb
ber of QALYs gain
ned or lost depends on
th
he valuation of th
hese QALYs. Dim
minishing the age related QALYs, this
t
is
th
he decrease in quality
q
of life due
e to old age, deccreases the numb
ber of
Q
QALYs
gained, as
s could be expecte
ed.
T estimations co
The
oming from the Lidgren’s paper are
e fairly uniform an
nd do
n vary much in function of the different stages. W
not
We introduced a larger
l
d
decrement
in qua
ality of life due to
o increasing stage
e at diagnosis, with
w
3
s
scenarios:
(i) decrreasing stage II III and IV with 20%
%, (ii) decreasing stage
IIII and IV with 20
0% or (iii) decrea
asing stage IV with 20%. This ha
as the
e
effect
of increasing the number of QALYs gained, b
because there are
e also
g
gains
in QALYs du
ue to the stage sh
hift alone outside the effect on morrtality,
a persons in stag
as
ge I have in this scenario a better a
assumed quality of
o life,
in
n contrast to the Lidgren
L
data.
A could be expec
As
cted, introducing discount
d
rates decreases the numb
ber of
Q
QALYs
gained.
A a worst case scenario,
As
s
we set th
he estimation of o
over diagnosis at 20%,
re
ecall rate at 10%
%, loss of QALYs per recall at 0.19
9 during a period of 54
d
days
and using th
he stage distributiion coming from the Flemish screening
p
program
(scenario
o 2). This gives a gain of 872 Years of Life but a lo
oss of
3 QALYs per 10
307
00 000.
A a best case sc
As
cenario, we set the estimation of over-diagnosis at 3%,
re
ecall rate at 2%, loss of QALYs per
p recall at 0.13 during a period of 36
d
days
and using th
he stage distribution coming from
m the Dutch screening
p
program
(scenario
o 1). This gives a gain of 1704 Years of Life and a gain of
1626 QALYs per 100
1 000.
A
Applying
the 22%
% reduction in mortality
m
from the meta-analysis from
G
Götzsche
et al. to
o the Belgian life table,
t
as describe
ed above, gives a very
s
similar
result, 139 cancers deaths due
d to breast can
ncer avoided and 1145
y
years
of life saved
d.
KCE Report 176
6
S
Screening
Breast Cancer
C
Table 3.3 Mode
eling results: bas
seline, worst and
d best case scen
nario.
Scenario
Assump
ptions
Years of life
Per 100 00
00
women
Quality ad
djusted years of life
l
Per 100 00
00
women
Baseline
Over
diagnosis:
10%
3.5%
3
recall
rate
at
QALYs per recall 0.16
loss of Q
during a period of 45 days
stage distribution com
ming
gram
Dutch screening prog
o 1)
(scenario
1307 gaine
ed
395 gained
d
Worst case
Over
diagnosis:
20%
recall
rate
at
10%
QALYs per recall 0.19
loss of Q
during a period of 54 days
stage distribution com
ming
gram
Flemish screening prog
o 2)
(scenario
872 gained
d
307 lost
Best case
Over
diagnosis:
3%
recall
rate
at
2%
QALYs per recall 0.13
loss of Q
during a period of 36 days
stage distribution com
ming
gram
Dutch screening prog
o 1)
(scenario
1704 gaine
ed
1626 gaine
ed
55
56
S
Screening
Breast Cancer
C
KCE Reportt 176
Table 3.4 Mode
eling results: sen
nsitivity analysis
s.
Stage
eshift
scena
ario 1
Stageshift
scenario 2
Sttageshift
sc
cenario 3
Years
s of life
QALYs
Years of life
QALYs
Ye
ears of life
QA
ALYs
1307
395
1014
186
12
246
420
0
0.03
1304
526
1011
317
12
245
551
1
0.05
1305
489
1012
280
12
245
514
4
0.1
1307
395
1014
186
12
246
420
0
0.2
1310
208
1018
0
12
249
232
2
0.3
1314
22
1022
-187
12
251
45
0.02
1307
442
1014
234
12
246
459
9
0.035
1307
395
1014
186
12
246
420
0
0.05
1307
348
1014
139
12
246
380
0
0.1
1307
190
1014
-19
12
246
249
9
36 days
1307
417
1014
208
12
246
438
8
45 days
1307
395
1014
186
12
246
420
0
54 days
1307
373
1014
164
12
246
401
1
QALYs loss pe
eriod 13%
1307
416
1014
207
12
246
449
9
QALYs loss pe
eriod 16%
1307
395
1014
186
12
246
434
4
QALYs loss pe
er period 19%
1307
374
1014
166
12
246
420
0
1120
281
869
102
na
a
na
Baseline
Assumed overrdiagnosis
Recall rate
Period betwee
en false positive
e and confirmation test:
duration
Period betwee
en false positive and confirmatio
on test:%
QALYs lost
Participation rate
r
0.6
KCE Report 176
6
S
Screening
Breast Cancer
C
57
0.7
1307
395
1014
186
na
a
na
0.8
1493
509
1159
270
na
a
na
0.6
1120
281
869
102
na
a
na
0.7
1307
395
1014
186
na
a
na
0.8
1493
509
1159
270
na
a
na
Dutch survivall
1607
710
1181
310
14
481
505
5
Britisch surviv
val
1714
399
1148
-3
15
585
374
4
Belgian surviv
val supplemented
d by French data
a
1460
473
1045
96
13
365
477
7
Assumed lead
d time 3 years
1098
118
875
77
11
169
187
7
All QALYs min
nus 20%
1307
-948
1014
-1089
12
246
-787
All QALYs plus
s 20%
1307
1587
1014
1310
12
246
153
34
Stage II III IV -2
20
1307
903
1014
465
12
246
na
Stage III IV -20
0
1307
648
1014
370
12
246
na
Stage IV -20
1307
450
1014
241
12
246
na
Discount rate 1.5% for QALYs
1307
297
1014
121
12
246
274
4
Discount rate 3%
3 for QALYs
1307
215
1014
67
12
246
193
3
Discount rate 5%
5 for QALYs
1307
138
1014
15
12
246
114
4
Effectiveness screening amon
ngst participants
Survival curve
e by stage from o
other sources
Discounted QA
ALYs
58
S
Screening
Breast Cancer
C
3.5. Discussion
Under baseline
e assumptions, sscreening in the age group 70-74
4 has a
limited impact on
o breast cancer d
deaths avoided and number of yea
ars of life
saved, amountiing to 1.4 death a
avoided per 1000 women offered sc
creening
in that period an
nd 13 years of life
e saved per 1000 women, amountin
ng to 4.7
days of life gain
ned per women offfered screening.
This results falll within the range
e that the modele
ers of the CISNET
T project
found as reportted by Mandelblattt et al in 200948, where
w
years of life
e gained
ranged from 9 to
t 22 per thousan
nd women screen
ned. This, despite the fact
that completely
y different data and
d model structures were used.
Years of life ga
ained remained fairly constant in the sensitivity analy
ysis. We
choose a worstt and best case sscenario, with yea
ars of life gained ranging
from 872 to 170
04. It correspondss also with the sim
mplified estimatio
on based
on the meta-analysis of Götzsche et al.4 and the Belgian
B
life tables,, despite
ation comes from a completely diffferent source of data
d
and
that this estima
estimation meth
hod. This indicate
es that the estima
ations of the years of life
gained are fairly
y robust and conssistent with other studies.
s
The gain in quality adjusted life years (QALYs) is
i considerably le
ess, with
Ys per 1000 wom
men (1.4 quality adjusted day of life per
only 3.9 QALY
women) offered
d screening and uncertainty is large
er. One can prese
ent these
data in anothe
er way by statin
ng that 250 wom
men need to be offered
screening for 5 years to gain one year of life. The sensitivity analysis
shows that und
der certain assumptions introducing
g breast cancer sc
creening
in this age gro
oup would actuallly generate a lo
oss of QALYs. Th
he most
important of these is an assum
med recall rate off 10%, as is the case in
es should certainly
y first be
certain parts off Belgium, so thesse high recall rate
ore proceeding.
addressed befo
The worst case
e scenario would imply a loss of 3 QALYs per 1000
0 women
screened, we made
m
sure that the assumptions off this worst case scenario
s
are still reason
nable assumption
ns and not unduly extreme. A nu
umber of
elements were not considered in the worst cas
se scenario beca
ause the
aseline estimation
n for the
effect is sometimes mixed. Bringing down the ba
p age-group inccreases or decrea
ases the final nu
umber of
quality of life per
QALYs gained depending on the chosen values of the other para
ameters.
ng induces losses
s due to
This is due to the fact that intrroducing screenin
a over diagnosiis but gains due to
o the stage shift.
false positives and
KCE Reportt 176
Under the best ca
U
ase scenario one would
w
gain 16 QA
ALYs per 1000 wo
omen
s
screened.
T
The
higher variab
bility seen in the estimation of the
e QALYs comparred to
y
years
of life lost has a numbe
er of reasons. T
There is conside
erable
u
uncertainty
around key parameterrs that determine
e a loss of QALY
Ys, in
p
particular
concern
ning over-diagnosis. Variability due
e to recall rates on
o the
o
other
hand rather reflects real und
derlying difference
es in practice bettween
c
countries
and in Belgium between regions. There
e is also conside
erable
u
uncertainty
around
d the valuation off the quality of liffe, and this is nott only
u
uncertainty
conce
erning the quality of life surroun
nding different breast
b
c
cancer
states but also age specific quality of life in B
Belgium. If in the future
f
c
cost-effectiveness
analyses are considered, thiss problem should be
a
addressed
if we want
w
to have mea
aningful results. Q
Quality of life attrib
buted
to
o stage IV has on
nly a limited impact on overall num
mbers of QALYs gained
o lost as survival in this stage is short and proportio
or
on of stage IV pa
atients
is
s low.
C
Carles
et al. 201138, in an adaptation of the CISNET model of Lee
L
&
Z
Zeelen,
found an incremental bene
efit for biannual sccreening 50-74 off 2.78
life years gained per
p 1000 women compared
c
to a sch
hedule 50-69. The
ey did
n report the QA
not
ALYs gained with extending the sccreening to 50-74 from
5
50-69,
as it was dominated by screening from 45-- 69, but reported
d that
1.86 QALYs per 1 000 were gaine
ed by extending tthe screening to 45-74
4
estingly, they did not
n incorporate th
he results of Vilap
prinyo
frrom 45-69. Intere
e al, 201158 into th
et
heir calculations, but used US survvival data.
T model takes into account over--diagnosis and lea
The
ad time bias. How
wever,
itt does not take into account leng
gth bias, the factt that screen-detected
c
cancers
would ha
ave a slower clinical course and have a better su
urvival
b
because
screening tends to pick-u
up slow growing ttumors some of which
w
a not life threate
are
ening. Follow up studies
s
of screen detected cancers
s and
n
non
screen detectted cancer in the
e literature show tthat survival of sc
creen
d
detected
cases is better than case
es among non parrticipants, indepen
ndent
o stage, and thatt survival of interv
of
val cases is somewhat in between
n88-91.
T
This
indicates tha
at there may ind
deed be a lengtth time bias, thrrough
s
selection
of less aggressive
a
cancers by screening. However, the fac
ct that
in
nterval cancers have
h
a better su
urvival than cance
er among women not
a
attending
screenin
ng indicates that other factors also
o play a role, suc
ch as
KCE Report 176
6
S
Screening
Breast Cancer
C
selection bias (such as the so
ocial class or other health related
d factors
en non attending screening) and re
esidual confounding after
amongst wome
adjustment for stage.
s
However le
ength time has no
o direct impact on efficacy
and on effectiveness, as dete
ection of slow grrowing tumors does not
gatively correlate
e with the ability to detect potentiially lifenecessarily neg
threatening can
ncers at an earlierr stage. Length tim
me has indeed a negative
n
impact on effic
ciency, as detection of indolent tu
umors means mo
ore harm
and greater cos
st for no benefit to
o women.
We unfortunate
ely did not have data on stage spec
cific survival for tu
umors in
unscreened wo
omen, tumors fo
ound by screenin
ng and interval cancers.
c
Moreover, there
e is in general co
onsiderable uncerttainty around the survival
curves that will apply in the future, as treatment ev
volves and actual data on
e outdated.
survival may be
Another majorr source of unccertainty is the right choice of
o stage
distributions of the diagnosed ccancers and stage
e-shift. The Flemish data
at the stage disttributions of the interval
on stage distribution show tha
o do not participatte in the
cancers and the cancer amongsst the people who
v
similar.
screening are very
We choose a modeling
m
approacch that is essenttially based on th
he stage
shift and its co
onsequences, in ccontrast to most CISNET models that are
essentially tumo
or growth modelss. This has the adv
vantage that it allo
owed us
to stay closer to the data and make less use of unobserved va
ariables,
arameters based on Belgian data, but has the disad
dvantage
incorporating pa
that the model is less flexible an
nd has more simp
plifications. We model
m
an
o screening on tthe proportion of cancers that are
e screen
overall effect of
detected based
d on Belgian data
a in the group 50-69. This implies that we
can only evalua
ate the effect of th
he screening sche
edules actually in place in
Belgium, we ca
annot vary the screening interval. We
W do not have the data
however neede
ed to parameterize
e the CISNET mo
odels and would be
b forced
to use the same
e parameters thatt are already used
d in the published models,
we would just merely
m
replicate th
hem.
In conclusion, there
t
is considera
able structural uncertainty around the right
choice of the parameters,
p
so a lot of caution is needed
n
when inte
erpreting
the results. This uncertainty is reflected in the wide range of es
stimated
g
and QALY
Ys gained in the end
e
result. Neverrtheless,
Years of Life gained
there is evidence that continuing
g screening until the age of 74 ye
ears has
59
modest effect on the
m
t number of Life
e Years Saved bu
ut there is conside
erable
u
uncertainty
on the
e effect on quality
y adjusted life yea
ars, and the data show
th
hat under reason
nable assumptions the intervention
n may even lead
d to a
lo
oss of quality adju
usted life years. Itt is important to b
bring the recall rattes to
a
acceptable
level before extending screening.
s
60
S
Screening
Breast Cancer
C
4. ANSW
WER TO CL
LINICAL QU
UESTIONS
S
What are clin
nical benefits an
nd specific harm
ms of an exten
nsion of
breast cancerr organized scre
eening in wome
en between 70 and 74
years?
4.1. Breast cancer related
d mortality
What is the effe
ect of an extension (70-74 years) of breast cancer orrganized
screening on th
he breast cancer rrelated mortality? The continued sc
creening
for breast canc
cer between the ages of 70 and 74 makes it pos
ssible to
obtain an extra 13 years of life fo
or 1,000 women screened.
s
The mo
odel also
28 deaths would be averted per 100 000 women screened
s
predicts that 12
(1.3 per 1000), being a reduction
n of 21%.
4.2. Delay between
b
the sccreening and th
he mortality red
duction
How long is the delay between the screening and the associated
d breast
d mortality reducction? The morttality reduction appears
cancer related
between 4 and 7 years after scre
eening
4.3. Overall mortality
What is the effe
ect of an extension (70-74 years) of breast cancer orrganized
screening on the
t
overall morta
ality? The effect of an extension
n (70-74
years) of breas
st cancer organizzed screening on
n the overall mo
ortality is
unclear. Studie
es did not have statistical powerr to detect an all-cause
a
mortality reducttion.
4.4. Morbidity
What is the effe
ect of an extension (70-74 years) of breast cancer orrganized
screening on morbidity?
m
We found no data relate
ed to the cancer morbidity
m
in randomized control
c
trials. In other words, on this basis we do no
ot accept
or reject the hy
ypothesis that scre
eening reduces th
he morbidity of the breast
cancer disease. Aim of screening is to detect minor tumors. Conse
equently,
b diminish by lesss aggressive treatment. The Belg
gian data
morbidity may be
currently at ourr disposal do not enable us to ratiffy this assertion. Actually,
A
the most recentt data (KCE reporrt 150)86 show 58%
% of the interventtions are
conservative surgery
s
versus 3
38% of total ma
astectomies in th
he least
advanced stage
es (C Stage I an
nd II). Nearly 90%
% of patients und
dergoing
KCE Reportt 176
conservative surge
c
ery also receive radiotherapy treatm
ment, 38% are giv
ven a
trreatment of neo
o-adjuvant chemo
otherapy, and 41% receive hormone
trreatment.
4
4.5.
False pos
sitive or false negative
n
resultss
What are the spe
W
ecific harms in te
erms of false possitive or false neg
gative
re
esults? The Belg
gian data currently
y at our disposall show a recall ra
ate of
3
3,5%
in Flanders
s and of 10% in Walloon and Brussels region
n per
s
screening
round. At
A this age group, performance of mammography is
s high
a rates of false negative results are
and
a relatively low. For USA, rate off false
n
negative
results are 1.5 per 100
00 women aged 70 to 79 years
s per
s
screening
round (B
BCSC-USA).
4
4.6.
Additiona
al diagnostic tes
sts
What are the spec
W
cific harms in term
ms of additional dia
agnostic tests? Tw
wenty
to
o forty additional punctures or biop
psies may be expe
ected per 1000 wo
omen
o
offered
screening (three rounds).
4
4.7.
Over-diag
gnosis and ove
er-treatment
What are the sp
W
pecific harms in
n terms of overr-diagnosis and overtrreatment? Based
d on selected studies, over-detecction (excluding DCIS
c
cases),
ranged fro
om (7% to 21%) to
o 35% (no data sp
pecific for women aged
7 to 79 years are
70
a available). Götzsche
G
reported
d that the numb
ber of
m
mastectomies
and
d lumpectomies was
w significantly llarger in the scre
eened
g
groups
(no data specific
s
for wome
en aged 70 to 79
9 years are availa
able).
T
Three
trials with adequate
a
randomiization showed a significant increa
ase in
m
mastectomies
and
d lumpectomies (R
Relative Risk (RR
R) 1.31, 95% (CI)) 1.22
to
o 1.42). Two trials with suboptimal randomizatio
on showed the same
in
ncrease in interve
entions (RR of 1.4
42 (95% CI 1.26 to
o 1.61)). The RR for
f all
fiive trials combined was 1.35 (95% CI 1.26 to 1.44).
KCE Report 176
6
S
Screening
Breast Cancer
C
4.8. What attitude
a
should be recommend
ded for women
n in
case off self referral?
It is advisable that when a pattient asks her doctor for a screen
ning, the
d
a strategyy minimizing the drawbacks
d
of scre
eening92.
doctor should develop
In this way, an attitude stru
uctured around three phases can be
recommended:
•
n specific to the ag
ge bracket93
Information
•
Decision making
m
according tto the patient pers
sonal assessmentt94
•
Steering off the person who
o so wishes towarrds a screening involving
methods th
hat minimize the d
drawbacks.
The criteria deffined in the frame
ework of the European Programme
e notably
make provision for the monitorin
ng of the technical quality of the eq
quipment
ble reading of the
e mammographies
s, and an optimiz
zation of
used, the doub
the recall rate955. In Belgium, the
e approved mamm
mography units meet
m
the
criteria laid dow
wn in the contexxt of the Europea
an Programme, and
a
it is
therefore logica
al to steer those w
women who explicitly request a sc
creening
towards these structures.
s
61
62
S
Screening
Breast Cancer
C
5. REFER
RENCES
1.
2.
3.
4.
5.
6.
7.
Paulus D, Mambourg F
F, Bonneux L. [B
Breast cancer scrreening].
Good Clinical Practice (GCP). Brussells: Belgian Health Care
edge Centre (KC
CE); 2005 02/05
5/2005. KCE rep
ports 11
Knowle
Availab
ble
from:
http://kc
ce.fgov.be/index_
_en.aspx?SGREF=5221&CREF=93
348
Verleye
e L, Desomer A, Gailly J, Robays
s j. [Identifying wo
omen at
risk fo
or breast cance
er/technical meth
hods for breast cancer
screeniing]. Good clinical Practice (GCP). Bruxelles: Centre
e fédéral
d'experrtise des soins d
de santé (KCE); 2012. KCE Repo
orts 172
Availab
ble
from:
http://w
www.kce.fgov.be/p
publication/report/identifying-women
n-atrisk-for--breast-cancertecchnical-methods-fo
or-breast-cancer-s
sc
Mambo
ourg F, Robays j,, Camberlin C, Vlayen J, Gailly J.. [Breast
cancer screening with m
mammography forr women in the agegroup
49 years ]. Good Clinical Practice (GCP). Brussels: Belgian
of 40-4
Health Care Knowledge
e Centre (KCE); 2010 07/07/201
10. KCE
129
9
Available
reports
from:
ce.fgov.be/index_
_en.aspx?SGREF=14851&CREF=1
16581
http://kc
Gotzsche PC, Nielsen M. Screening for breast canc
cer with
ography. Cochra
ane Database of
o Systematic Reviews.
R
mammo
2011(1).
Nelson HD, Tyne K, Naik A, Bougatsos C,
C Chan BK, Humphrey L.
ancer: an update
e for the U.S. Pre
eventive
Screening for breast ca
es Task Force. Ann Intern Me
ed. 2009;151(10):727-37,
Service
W237-4
42.
Biesheuvel C, Barratt A, Howard K, Houss
sami N, Irwig L. Effects
E
of
m
and biasses on estimates of invasive breas
st cancer
study methods
overdettection with mammography screen
ning: a systematic
c review.
Lancet Oncol. 2007;8(12
2):1129-38.
Jorgens
sen KJ, Götzsche
e PC. Overdiagno
osis in publicly orrganised
mammo
ography screening programmes: systematic review of
incidence trends. Bmj. 20
009;339.
8
8.
9
9.
10.
11.
12.
13.
14.
15.
16.
17.
KCE Reportt 176
Virnig BA,, Tuttle TM, Sham
mliyan T, Kane RL
L. Ductal carcinom
ma in
situ of the breast: a system
matic review of inccidence, treatmentt, and
nst. 2010;102(3):170-8.
outcomes. J Natl Cancer In
Humphrey
y LL, Helfand M, Chan BK, Woo
olf SH. Breast ca
ancer
screening: a summary of the evidence for the U.S. Preve
entive
T
Force. Ann Intern Med. 2002;137(5 Part 1):347
7-60.
Services Task
Tabar L, Fagerberg CJ, Gad A, Baldeto
orp L, Holmberg
g LH,
O et al. Reductio
on in mortality fro
om breast cancerr after
Grontoft O,
mass scre
eening with mam
mmography. Rand
domised trial from
m the
Breast Ca
ancer Screening Working
W
Group off the Swedish National
Board of Health
H
and Welfarre. Lancet. 1985;1
1(8433):829-32.
Dixon JM
M. Breast screening has increa
ased the numbe
er of
mastectom
mies. Breast Canc
cer Res. 2009;11 Suppl 3:S19.
Smith RA, Duffy SW, Gabe R, Tabar L, Ye
en AM, Chen TH. The
ed trials of brea
ast cancer scree
ening: what have
e we
randomize
learned? Radiol
R
Clin North Am. 2004;42(5):7
793-806, v.
Nystrom L,
L Andersson I, Bjurstam N, Frise
ell J, Nordenskjo
old B,
Rutqvist LE. Long-term effects of mam
mmography scree
ening:
omised trials. La
ancet.
updated overview of the Swedish rando
2002;359((9310):909-19.
Tabar L, Vitak B, Chen TH,
T
Yen AM, Co
ohen A, Tot T, et al.
T
Triall: Impact of Mam
mmographic Screening
Swedish Two-County
on Breast Cancer Mortality during 3 Decadess. Radiology. 2011.
Maass N, Alkasi O, Baue
er M, Jonat W, S
Souchon R, Mein
nholdment of ductal ca
arcinoma in situ of
o the
Heerlein I. Actual managem
ch Gynecol Obste
et. 2009;280(5):69
99-705.
breast. Arc
Duffy SW,, Chen HH, Tabarr L, Day NE. Estim
mation of mean so
ojourn
time in brreast cancer scre
eening using a M
Markov chain mod
del of
both entry
y to and exit from
m the preclinical d
detectable phase. Stat
Med. 1995
5;14(14):1531-43..
Frachebou
ud J, Groenewoud
d JH, Boer R, Dra
aisma G, de Bruijn AE,
Verbeek AL,
A et al. Seventy
y-five years is an appropriate uppe
er age
limit for po
opulation-based mammography
m
sccreening. Int J Ca
ancer.
2006;118((8):2020-5.
KCE Report 176
6
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
S
Screening
Breast Cancer
C
Fett MJ
J. Computer mod
delling of the Sw
wedish two county
y trial of
mammo
ographic screenin
ng and trade offs between
b
participa
ation and
screeniing interval. Journ
nal of Medical Scre
eening. 2001;8(1)):39-45.
Shen Y, Zelen M. R
Robust modeling
g in screening studies:
estimattion of sensitivityy and preclinical sojourn time disttribution.
Biostatistics. 2005;6(4):6
604-14.
Wu JC, Hakama M, Antttila A, Yen AM, Malila
M
N, Sarkeala T, et al.
o breast cancer based
b
on
Estimattion of natural history parameters of
non-ran
ndomized organizzed screening data: subsidiary ana
alysis of
effects of inter-screening
g interval, sensitivity, and attendance rate
earch &
on reduction of advancced cancer. Breast Cancer Rese
Treatment. 2010;122(2):553-66.
OF, Myles JP, Lynge E, Dufffy SW.
Olsen AH, Agbaje O
agnosis, sojourn time, and sensittivity in the Cope
enhagen
Overdia
mammo
ography
scree
ening
program
m.
Breast
Journal.
2006;12
2(4):338-42.
Frisell J, Eklund G, He
ellstrom L, Somell A. Analysis of interval
eening trial in Sto
ockholm.
breast carcinomas in a randomized scre
h & Treatment. 19
987;9(3):219-25.
Breast Cancer Research
E Duffy SW. M
Modelling the analysis of breast cancer
Paci E,
screeniing programmes: sensitivity, lead time
t
and predictiv
ve value
in the Florence Districct Programme (1
1975-1986). Interrnational
Journal of Epidemiology. 1991;20(4):852-8.
R de Koning H
HJ, van der Maa
as PJ. A longerr breast
Boer R,
carcino
oma screening interval for women age older than 65
5 years?
Cancerr. 1999;86(8):1506
6-10.
Duffy SW,
S
Day NE, Tabar L, Chen HH, Smith
S
TC. Markov
v models
of brea
ast tumor progresssion: some age-s
specific results. Jo
ournal of
the Nattional Cancer Insttitute. Monographs
s. 1997;22:93-7.
Duffy SW,
S
Gabe R. Wha
at should the dete
ection rates of can
ncers be
in brea
ast screening programmes? Brittish Journal of Cancer.
2005;92
2(3):597-600.
Shen Y,
Y Zelen M. Scre
eening sensitivity
y and sojourn tim
me from
breast cancer early de
etection clinical trrials: mammogra
ams and
2
28.
2
29.
3
30.
3
31.
3
32.
3
33.
3
34.
3
35.
3
36.
3
37.
63
physical
examinations.
Journal
of
Clinical
Onco
ology.
2001;19(15):3490-9.
Spratt JS, Greenberg RA, Heuser
H
LS. Geom
metry, growth rates
s, and
o cancer and ca
arcinoma in situ of the breast before
b
duration of
detection by screening. Can
ncer Research. 19
986;46(2):970-4.
Tabar L, Fagerberg
F
G, Che
en HH, Duffy SW, Smart CR, Gad A, et
al. Efficac
cy of breast cance
er screening by a
age. New results from
the Swedish Two-County Trial. Cancer. 1995
5;75(10):2507-17..
Weedon-F
Fekjaer H, Lindqv
vist BH, Vatten LJ, Aalen OO, Tre
etli S.
Estimating
g mean sojourn time and scree
ening sensitivity using
questionna
aire data on time
e since previous screening. Journ
nal of
Medical Screening. 2008;15
5(2):83-90.
Weedon-F
Fekjaer H, Vatten
n LJ, Aalen OO, Lindqvist B, Tre
etli S.
Estimating
g mean sojourn time and screen
ning test sensitiv
vity in
breast cancer mammograp
phy screening: new results. Journ
nal of
2(4):172-8.
Medical Screening. 2005;12
Zappa M, Visioli CB, Ciatto
o S. Mammograph
hy screening in elderly
e
e
and cost--effectiveness. Re
eview 16 refs. Critical
C
women: efficacy
Reviews in
n Oncology Hema
atology. 2003;46(3
3):235-9.
Boer R, de Koning HJ, van
n Oortmarssen GJJ, van der Maas PJ.
P In
ge limit for breast cancer screening
g. Eur
search of the best upper ag
J Cancer. 1995;31A(12):2040-3.
Mandelbla
att JS, Silliman R. Hanging in the balance: making
decisions about the benefits
s and harms of brreast cancer screening
e oldest old witho
out a safety net o
of scientific eviden
nce. J
among the
Clin Oncol. 2009;27(4):487--90.
Karnon J, Goyder E, Tappe
enden P, McPhie S, Towers I, Braz
zier J,
ng in prioritising and
et al. A review and crittique of modellin
ogrammes. Heallth Technol As
ssess.
designing screening pro
52):iii-iv, ix-xi, 1-14
45.
2007;11(5
Barratt A, Howard K, Irwig
g L, Salkeld G, H
Houssami N. Mod
del of
m
in
nformation to su
upport
outcomes of screening mammography:
c
BMJ. 200
05;330(7497):936
6.
informed choices.
Berry DA,, Inoue L, Shen Y,
Y Venier J, Cohen D, Bondy M, et al.
Modeling the impact of tre
eatment and scre
eening on U.S. breast
b
64
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
S
Screening
Breast Cancer
C
cancer mortality: a Baye
esian approach. J Natl Cancer Inst Monogr.
Monographs.(36):3
30-6.
2006;M
Carles M, Vilaprinyo E, Cots F, Gregori A,
A Pla R, Roman R, et al.
arly detection of breast
b
cancer in Catalonia
C
Cost-efffectiveness of ea
(Spain)). BMC Cancer. 20
011;11.
Carter KJ, Castro F, Ke
essler E, Erickson
n BA. Simulation of begin
nd ages for mammography scre
eening. J Health
hc Qual.
and en
2005;27
7(1):40-7.
Feuer EJ.
E Modeling the impact of adjuva
ant therapy and sc
creening
mammo
ography on U.S. breast cancer mo
ortality between 1975 and
2000: introduction to th
he problem. J Natl Cancer Inst Monogr.
Monographs.(36):2
2-6.
2006;M
Fryback DG, Stout N
NK, Rosenberg MA, Trentham-D
Dietz A,
ngton PL. The Wisconsin
W
Breast Cancer
Kuruchittham V, Remin
miology Simulatio
on Model. J Na
atl Cancer Inst Monogr.
Epidem
2006;M
Monographs.(36):3
37-47.
Gyrd-H
Hansen D. Cost-be
enefit analysis of mammography sc
creening
in Denm
mark based on diiscrete ranking da
ata. Int J Technoll Assess
Health Care. 2000;16(3):811-21.
Hanin LG, Miller A, Zo
orin AV, Yakovlev AY. The Unive
ersity of
ster model of bre
east cancer detec
ction and survival. J Natl
Roches
Cancerr Inst Monogr. 200
06;Monographs.(3
36):66-78.
Lee S, Zelen M. A stoch
hastic model for predicting
p
the mo
ortality of
cancer.
J
Natl
Can
ncer
Inst
breast
Monogr.
Monographs.(36):7
79-86.
2006;M
Lee SJ
J, Zelen M. Mode
elling the early de
etection of breast cancer.
Ann On
ncol. 2003;14(8):1199-202.
Mahnke
en JD, Chan W, Freeman DH, Jr., Freeman JL. Reducing
R
the effe
ects of lead-time
e bias, length bia
as and over-dete
ection in
evaluatting screening m
mammography: a censored bivaria
ate data
approach. Stat Methods Med Res. 2008;17(6):643-63.
Mandelblatt J, Schechte
er CB, Lawrence W, Yi B, Cullen
n J. The
TRUM population
n model of the impact of screen
ning and
SPECT
treatme
ent on U.S. bre
east cancer trend
ds from 1975 to
o 2000:
4
48.
4
49.
5
50.
5
51.
5
52.
5
53.
5
54.
5
55.
KCE Reportt 176
principles and practice of the
t
model method
ds. J Natl Cance
er Inst
2
.(36):47-55.
Monogr. 2006;Monographs
Mandelbla
att JS, Cronin KA
A, Bailey S, Berrry DA, de Koning
g HJ,
Draisma G, et al. Effects of mammogra
aphy screening under
u
dules: model esstimates of pottential
different screening sched
m appears in Ann
n Intern Med. 2010
0 Jan
benefits and harms.[Erratum
0):738-47.
19;152(2)::136]. Ann Intern Med. 2009;151(10
Mandelbla
att JS, Schechter CB, Yabroff KR, Lawrence W, Dig
gnam
J, Exterm
mann M, et al. To
oward optimal sccreening strategie
es for
older wom
men: Costs, benefits, and harm
ms of breast ca
ancer
screening by age, biology, and health statuss. J. Gen. Intern. Med.
6):487-96.
2005;20(6
Neeser K,, Szucs T, Bulliard
d JL, Bachmann G, Schramm W. Costeffectivene
ess analysis off a quality-conttrolled mammogrraphy
screening program from
m the Swiss statutory health
h-care
ve: quantitative as
ssessment of the most influential fa
actors
perspectiv
(Structured abstract). 2007;;10(1):42-53.
Plevritis SK,
S
Sigal BM, Salzman
S
P, Rose
enberg J, Glynn P. A
stochastic
c simulation mode
el of U.S. breast ccancer mortality trrends
from 19
975 to 2000. J Natl Cancer Inst Mo
onogr.
2006;Monographs.(36):86-9
95.
Rauner MS,
M Gutjahr WJ, Heidenberger K, Wagner J, Pas
sia J.
Dynamic Policy Modeling for Chronic Disseases: Metaheuristicdentification of Pareto-Optimal
P
S
Screening Strate
egies.
Based Id
Operations Research. 2010
0;58(5):1269-86.
Rijnsburge
er AJ, van Oortm
marssen GJ, Boerr R, Draisma G, To
T T,
Miller AB, et al. Mammogrraphy benefit in tthe Canadian National
creening Study-2
2: a model evaluation. Int J Ca
ancer.
Breast Sc
2004;110((5):756-62.
Rojnik K, Naversnik K, Mateovic-Rojnikk T, Primiczakelj M.
ness modeling of different breast ca
ancer
Probabilistic cost-effectiven
nia. Value Health. 2008;11(2):139-4
48.
screening policies in Sloven
Rue M, Vilaprinyo
V
E, Lee
e S, Martinez-Allonso M, Carles MD,
Marcos-Gragera R, et al. Efffectiveness of ea
arly detection on breast
b
KCE Report 176
6
56.
57.
58.
59.
60.
61.
62.
63.
64.
65.
S
Screening
Breast Cancer
C
cancer mortality reducttion in Catalonia
a (Spain). BMC Cancer.
2009;9(326).
N Rosenberg MA
A, Trentham-Diettz A, Smith MA, Robinson
R
Stout NK,
SM, Frryback DG. Retrrospective cost-e
effectiveness ana
alysis of
screeniing mammography. J Natl Cancer Inst.
I
2006;98(11):774-82.
Tan SY
Y, van Oortmarsssen GJ, de Konin
ng HJ, Boer R, Habbema
H
JD. The
e MISCAN-Fadia continuous tumor growth model fo
or breast
cancer.. J Natl Cancer Inst Monogr. 2006;M
Monographs.(36):56-65.
Vilaprin
nyo E, Rue M, Marcos-Gragera R, Martinez-Alo
onso M.
Estimattion of age- an
nd stage-specific Catalan breast cancer
surviva
al functions using
g US and Cata
alan survival data
a. BMC
Cancerr. 2009;9(98).
Wang H, Karesen R, Hervik A, Thore
esen SA. Mamm
mography
esults from the firs
st screening round in four
screeniing in Norway: Re
countie
es and cost-efffectiveness of a modeled nationwide
screeniing. Cancer Causes Control. 2001;12(1):39-45.
Messec
car DC. Mammog
graphy screening for
f older women with
w and
withoutt cognitive impairrment. J Gerontoll Nurs. 2000;26(4
4):14-24;
quiz 52
2-3.
Wen YP
P, Sheu ML. A co
ost-benefit analysis of preventive ca
are: The
case of
o breast cancer screening. Taiwain J. Public Health.
2005;24
4(6):519-28.
Advisorry Committee on
n Breast Cancer S. Screening fo
or breast
cancer in England: past and future. J Me
ed Screen. 2006;1
13(2):5961.
Anonym
mous. Landelijk bevolkingsonderrzoek naar bors
stkanker
volledig
g ingevoerd; resultaten van de implementatiefase
e 19901997. Landelijk
L
Evaluattie Team voor be
evolkingsonderzo
oek naar
Borstka
anker. Ned Tijdsch
hr Geneeskd. 200
00;144(23):1124-9
9.
Barratt A, Irwig L, Glasziiou P, Salkeld G, Houssami N, Kerllikowske
y reduces with age. Evid.K, et al. Relative benefit of mammography
4):156-7.
Based Healthc. 2002;6(4
M, Glasziou PP, Salkeld
S
GP, Hous
ssami N.
Barratt AL, Les Irwig M
m
in
n women
Benefits, harms and cossts of screening mammography
6
66.
6
67.
6
68.
6
69.
7
70.
7
71.
7
72.
7
73.
7
74.
7
75.
65
70 years
s and over: a systematic review. Med J Aust.
2002;176((6):266-71.
Bonneux L. De voor- en nadelen
n
van borsstkankerscreening
g: tijd
dence-based info
ormatie. Nederla
ands Tijdschrift voor
voor evid
Geneesku
unde. 2009;153.
Caplan LS
S. To screen or not to screen: the issue of breast ca
ancer
screening in older women.. Public Health R
Rev. 2001;29(2-4)):23140.
Carney PA
A, Abraham LA, Miglioretti DL, Ya
abroff KR, Sickles
s EA,
Buist DSM
M, et al. Factors associated
a
with im
maging and proce
edural
events used
u
to detec
ct breast canccer after screening
mammogrraphy. Am. J. Roe
entgenol. 2007;188(2):385-92.
De Koning
g HJ. Breast canc
cer screening; cosst-effective in prac
ctice?
Eur J Radiol. 2000;33(1):32
2-7.
Feuer EJ, Etzioni R, Cronin
n KA, Mariotto A. T
The use of modeling to
S. mortality: exam
mples
understand the impact of screening on U.S
mmography and PSA testing. Sta
at Methods Med Res.
from mam
2004;13(6
6):421-42.
Grivegnee
e AR, Autier P. Approche
A
econom
mique du depistag
ge du
cancer du sein en Belgique
e. Rev Med Brux. 2
2001;22(4):A277--81.
Habbema JD, Tan SY, Crronin KA. Impact of mammograph
hy on
st cancer mortality
y, 1975-2000: are
e intermediate outcome
U.S. breas
measures informative? J Natl Can
ncer Inst Mo
onogr.
5-11.
2006;Monographs.(36):105
Mandelbla
att J, Saha S, Teu
utsch S, Hoerger T, Siu AL, Atkins D, et
al. The co
ost-effectiveness of
o screening mammography beyond
d age
65 years: a systematic re
eview for the U.S
S. Preventive Serrvices
ce. Ann Intern Med
d. 2003;139(10):8
835-42.
Task Forc
Prevost TC,
T
Abrams KR
R, Jones DR. Hierarchical mode
els in
generalize
ed synthesis of ev
vidence: an exam
mple based on sttudies
of breast cancer
c
screening. Stat Med. 2000;1
19(24):3359-76.
Rautenstra
auch J. Is mam
mmography screening only a poin
ntless
waste of money?
m
MMW-Fortschr. Med. 2000
0;142(12):4-10.
66
76.
77.
78.
79.
80.
81.
82.
83.
84.
85.
86.
S
Screening
Breast Cancer
C
Xu W, Vnenchak P, S
Smucny J. Scre
eening mammogrraphy in
n aged 70 to 79 ye
ears. J. 2000;49(3
3):266-7.
women
Berry DA,
D Cronin KA, Ple
evritis SK, Frybac
ck DG, Clarke L, Zelen
Z
M,
et al. Effect
E
of screenin
ng and adjuvant therapy
t
on mortality from
breast cancer.
c
N Engl J Med. 2005;353(17
7):1784-92.
Carter KJ, Castro F, Kesssler E, Erickson B. A computer model
m
for
dy of breast cance
er. Comput Biol Med.
M
2003;33(4):345-60.
the stud
Cleemp
put I, Van Wilder P, Vrijens F, Huyb
brechts M, Ramae
ekers D.
Recommandations pour les évaluations pharmacoéconomi
p
iques en
ue. Health technology Assessment (HTA). Bruxelles
s: Centre
Belgiqu
fédéral d'expertise des ssoins de santé (K
KCE); 2008. KCE Reports
78B (D//2008/10.273/24)
Lidgren
n M, Wilking N, Jonsson B, Reh
hnberg C. Health
h related
quality of life in differen
nt states of breas
st cancer. Qual Life
L Res.
6(6):1073-81.
2007;16
Freedm
man GM, Li T, An
nderson PR, Nicolaou N, Konski A.
A Health
states of
o women after co
onservative surgerry and radiation fo
or breast
cancer.. Breast Cancer R
Res Treat. 2010;12
21(2):519-26.
Burstro
om K, Johannesso
on M, Diderichsen
n F. Health-related
d quality
of life by disease and
d socio-economic
c group in the general
Health Policy. 2001
1;55(1):51-69.
populattion in Sweden. H
Gerard K, Johnston K, Brown J. The ro
ole of a pre-score
ed multie health classifiication measure in validating co
onditionattribute
specific
c health state desccriptions. Health Econ.
E
1999;8(8):6
685-99.
Domey
yer PJ, Sergentan
nis TN, Zagouri F, Zografos GC. Healthrelated quality of life in vvacuum-assisted breast biopsy: sh
hort-term
y of Life
effects,, long-term effectts and predictors. Health & Quality
Outcom
mes. 2010;8(11):2
2010.
Borstka
anker
LETvb
bn.
Landelijke
e
evaluatie
van
bevolkingsonderzoek na
aar borstkanker in Nederland 199
90-2007.
2010.
ur S, Vrijens F, Beirens K, Vlay
yen J, Devriese S, Van
Stordeu
Eycken
n E. Quality indiccators in oncolog
gy: breast bance
er. Good
Clinicall Practice (GCP). Brussels: Belgian
n Health Care Knowledge
Centre (KCE); 2010. KCE reports 15
50C (D/2010/10.2
273/101)
8
87.
8
88.
8
89.
9
90.
9
91.
9
92.
9
93.
9
94.
9
95.
KCE Reportt 176
Available
from:
211&CREF=1884
47
http://kce.ffgov.be/index_en.aspx?SGREF=52
INC. Surv
vie attendue des patients
p
atteints d
de cancers en Fra
ance :
état des lie
eux. 2010.
Mook S, Van
V 't Veer LJ, Ru
utgers EJ, Ravdin PM, van de Velde
e AO,
van Leeuw
wen FE, et al. In
ndependent progn
nostic value of sc
creen
detection in invasive brreast cancer. J Natl Cancer Inst.
2011;103((7):585-97.
Cortesi L, Chiuri VE, Rusce
elli S, Bellelli V, N
Negri R, Rashid I, et al.
s of screen-dete
ected breast ca
ancers: results of a
Prognosis
population
n based study. BM
MC Cancer. 2006;6:17.
Joensuu H,
H Lehtimaki T, Ho
olli K, Elomaa L, T
Turpeenniemi-Hujjanen
T, Kataja V, et al. Risk fo
or distant recurre
ence of breast ca
ancer
hy screening or o
other methods. Jama.
J
detected by mammograph
2004;292((9):1064-73.
Olsson A, Borgquist S, Buttt S, Zackrisson S
S, Landberg G, Manjer
M
a prognosis in b
breast cancer detected
J. Tumourr-related factors and
by screening. Br J Surg. 20
012;99(1):78-87.
Physicians
s AAoF. Summa
ary of Recomme
endations for Cllinical
Preventive
e Services. In: AA
AFP Policy Action AAFP; 2010.
Woloshin S, Schwartz LM. The bene
efits and harm
ms of
AMA.
mammogrraphy screening: understanding tthe trade-offs. JA
2010;303((2):164-5.
Jorgensen
n KJ, Gotzsche PC. Content of invitations for pu
ublicly
funded screening mammog
graphy. BMJ. 2006
6;332(7540):538-4
41.
Perry N, Broeders
B
M, de Wolf
W C, Tornberg S, Holland R, von Karsa
K
L. Europe
ean guidelines fo
or quality assura
ance in breast ca
ancer
screening and diagnosis. Fourth
F
edition--sum
mmary documentt. Ann
08;19(4):614-22.
Oncol. 200
KCE Report 176
6
56.
57.
58.
59.
60.
61.
62.
63.
64.
65.
S
Screening
Breast Cancer
C
cancer mortality reducttion in Catalonia
a (Spain). BMC Cancer.
2009;9(326).
Stout NK,
N Rosenberg MA
A, Trentham-Diettz A, Smith MA, Robinson
R
SM, Frryback DG. Retrrospective cost-e
effectiveness ana
alysis of
screeniing mammography. J Natl Cancer Inst.
I
2006;98(11):774-82.
Tan SY
Y, van Oortmarsssen GJ, de Konin
ng HJ, Boer R, Habbema
H
JD. The
e MISCAN-Fadia continuous tumor growth model fo
or breast
cancer.. J Natl Cancer Inst Monogr. 2006;M
Monographs.(36):56-65.
Vilaprin
nyo E, Rue M, Marcos-Gragera R, Martinez-Alo
onso M.
Estimattion of age- an
nd stage-specific Catalan breast cancer
surviva
al functions using
g US and Cata
alan survival data
a. BMC
Cancerr. 2009;9(98).
Wang H, Karesen R, Hervik A, Thore
esen SA. Mamm
mography
screeniing in Norway: Re
esults from the firs
st screening round in four
countie
es and cost-efffectiveness of a modeled nationwide
screeniing. Cancer Causes Control. 2001;12(1):39-45.
Messec
car DC. Mammog
graphy screening for
f older women with
w and
withoutt cognitive impairrment. J Gerontoll Nurs. 2000;26(4
4):14-24;
quiz 52
2-3.
Wen YP
P, Sheu ML. A co
ost-benefit analysis of preventive ca
are: The
case of
o breast cancer screening. Taiwain J. Public Health.
2005;24
4(6):519-28.
Advisorry Committee on
n Breast Cancer S. Screening fo
or breast
cancer in England: past and future. J Me
ed Screen. 2006;1
13(2):5961.
Anonym
mous. Landelijk bevolkingsonderrzoek naar bors
stkanker
volledig
g ingevoerd; resultaten van de implementatiefase
e 19901997. Landelijk
L
Evaluattie Team voor be
evolkingsonderzo
oek naar
Borstka
anker. Ned Tijdsch
hr Geneeskd. 200
00;144(23):1124-9
9.
Barratt A, Irwig L, Glasziiou P, Salkeld G, Houssami N, Kerllikowske
K, et al. Relative benefit of mammography
y reduces with age. Evid.Based Healthc. 2002;6(4
4):156-7.
Barratt AL, Les Irwig M
M, Glasziou PP, Salkeld
S
GP, Hous
ssami N.
Benefits, harms and cossts of screening mammography
m
in
n women
6
66.
6
67.
6
68.
6
69.
7
70.
7
71.
7
72.
7
73.
7
74.
7
75.
67
70 years
s and over: a systematic review. Med J Aust.
2002;176((6):266-71.
Bonneux L. De voor- en nadelen
n
van borsstkankerscreening
g: tijd
voor evid
dence-based info
ormatie. Nederla
ands Tijdschrift voor
Geneesku
unde. 2009;153.
Caplan LS
S. To screen or not to screen: the issue of breast ca
ancer
screening in older women.. Public Health R
Rev. 2001;29(2-4)):23140.
Carney PA
A, Abraham LA, Miglioretti DL, Ya
abroff KR, Sickles
s EA,
Buist DSM
M, et al. Factors associated
a
with im
maging and proce
edural
events used
u
to detec
ct breast canccer after screening
mammogrraphy. Am. J. Roe
entgenol. 2007;188(2):385-92.
De Koning
g HJ. Breast canc
cer screening; cosst-effective in prac
ctice?
Eur J Radiol. 2000;33(1):32
2-7.
Feuer EJ, Etzioni R, Cronin
n KA, Mariotto A. T
The use of modeling to
understand the impact of screening on U.S
S. mortality: exam
mples
from mam
mmography and PSA testing. Sta
at Methods Med Res.
2004;13(6
6):421-42.
Grivegnee
e AR, Autier P. Approche
A
econom
mique du depistag
ge du
cancer du sein en Belgique
e. Rev Med Brux. 2
2001;22(4):A277--81.
Habbema JD, Tan SY, Crronin KA. Impact of mammograph
hy on
U.S. breas
st cancer mortality
y, 1975-2000: are
e intermediate outcome
measures informative? J Natl Can
ncer Inst Mo
onogr.
2006;Monographs.(36):105
5-11.
Mandelbla
att J, Saha S, Teu
utsch S, Hoerger T, Siu AL, Atkins D, et
al. The co
ost-effectiveness of
o screening mammography beyond
d age
65 years: a systematic re
eview for the U.S
S. Preventive Serrvices
Task Forc
ce. Ann Intern Med
d. 2003;139(10):8
835-42.
Prevost TC,
T
Abrams KR
R, Jones DR. Hierarchical mode
els in
generalize
ed synthesis of ev
vidence: an exam
mple based on sttudies
of breast cancer
c
screening. Stat Med. 2000;1
19(24):3359-76.
Rautenstra
auch J. Is mam
mmography screening only a poin
ntless
waste of money?
m
MMW-Fortschr. Med. 2000
0;142(12):4-10.
68
76.
77.
78.
79.
80.
81.
82.
83.
84.
85.
86.
S
Screening
Breast Cancer
C
Xu W, Vnenchak P, S
Smucny J. Scre
eening mammogrraphy in
women
n aged 70 to 79 ye
ears. J. 2000;49(3
3):266-7.
Berry DA,
D Cronin KA, Ple
evritis SK, Frybac
ck DG, Clarke L, Zelen
Z
M,
et al. Effect
E
of screenin
ng and adjuvant therapy
t
on mortality from
breast cancer.
c
N Engl J Med. 2005;353(17
7):1784-92.
Carter KJ, Castro F, Kesssler E, Erickson B. A computer model
m
for
the stud
dy of breast cance
er. Comput Biol Med.
M
2003;33(4):345-60.
Cleemp
put I, Van Wilder P, Vrijens F, Huyb
brechts M, Ramae
ekers D.
Recommandations pour les évaluations pharmacoéconomi
p
iques en
Belgiqu
ue. Health technology Assessment (HTA). Bruxelles
s: Centre
fédéral d'expertise des ssoins de santé (K
KCE); 2008. KCE Reports
78B (D//2008/10.273/24)
Lidgren
n M, Wilking N, Jonsson B, Reh
hnberg C. Health
h related
quality of life in differen
nt states of breas
st cancer. Qual Life
L Res.
2007;16
6(6):1073-81.
Freedm
man GM, Li T, An
nderson PR, Nicolaou N, Konski A.
A Health
states of
o women after co
onservative surgerry and radiation fo
or breast
cancer.. Breast Cancer R
Res Treat. 2010;12
21(2):519-26.
Burstro
om K, Johannesso
on M, Diderichsen
n F. Health-related
d quality
of life by disease and
d socio-economic
c group in the general
populattion in Sweden. H
Health Policy. 2001
1;55(1):51-69.
Gerard K, Johnston K, Brown J. The ro
ole of a pre-score
ed multiattribute
e health classifiication measure in validating co
onditionspecific
c health state desccriptions. Health Econ.
E
1999;8(8):6
685-99.
Domey
yer PJ, Sergentan
nis TN, Zagouri F, Zografos GC. Healthrelated quality of life in vvacuum-assisted breast biopsy: sh
hort-term
effects,, long-term effectts and predictors. Health & Quality
y of Life
Outcom
mes. 2010;8(11):2
2010.
van
Borstka
anker
LETvb
bn.
Landelijke
e
evaluatie
bevolkingsonderzoek na
aar borstkanker in Nederland 199
90-2007.
2010.
Stordeu
ur S, Vrijens F, Beirens K, Vlay
yen J, Devriese S, Van
Eycken
n E. Quality indiccators in oncolog
gy: breast bance
er. Good
Clinicall Practice (GCP). Brussels: Belgian
n Health Care Knowledge
Centre (KCE); 2010. KCE reports 15
50C (D/2010/10.2
273/101)
8
87.
8
88.
8
89.
9
90.
9
91.
9
92.
9
93.
9
94.
9
95.
KCE Reportt 176
Available
from:
http://kce.ffgov.be/index_en.aspx?SGREF=52
211&CREF=1884
47
INC. Surv
vie attendue des patients
p
atteints d
de cancers en Fra
ance :
état des lie
eux. 2010.
Mook S, Van
V 't Veer LJ, Ru
utgers EJ, Ravdin PM, van de Velde
e AO,
van Leeuw
wen FE, et al. In
ndependent progn
nostic value of sc
creen
detection in invasive brreast cancer. J Natl Cancer Inst.
2011;103((7):585-97.
Cortesi L, Chiuri VE, Rusce
elli S, Bellelli V, N
Negri R, Rashid I, et al.
Prognosis
s of screen-dete
ected breast ca
ancers: results of a
population
n based study. BM
MC Cancer. 2006;6:17.
Joensuu H,
H Lehtimaki T, Ho
olli K, Elomaa L, T
Turpeenniemi-Hujjanen
T, Kataja V, et al. Risk fo
or distant recurre
ence of breast ca
ancer
detected by mammograph
hy screening or o
other methods. Jama.
J
2004;292((9):1064-73.
Olsson A, Borgquist S, Buttt S, Zackrisson S
S, Landberg G, Manjer
M
J. Tumourr-related factors and
a prognosis in b
breast cancer detected
by screening. Br J Surg. 20
012;99(1):78-87.
Physicians
s AAoF. Summa
ary of Recomme
endations for Cllinical
Preventive
e Services. In: AA
AFP Policy Action AAFP; 2010.
Woloshin S, Schwartz LM. The bene
efits and harm
ms of
mammogrraphy screening: understanding tthe trade-offs. JA
AMA.
2010;303((2):164-5.
Jorgensen
n KJ, Gotzsche PC. Content of invitations for pu
ublicly
funded screening mammog
graphy. BMJ. 2006
6;332(7540):538-4
41.
Perry N, Broeders
B
M, de Wolf
W C, Tornberg S, Holland R, von Karsa
K
L. Europe
ean guidelines fo
or quality assura
ance in breast ca
ancer
screening and diagnosis. Fourth
F
edition--sum
mmary documentt. Ann
Oncol. 200
08;19(4):614-22.
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