Breast cancer mortality in mammographic screening in Europe: a review of incidence-based mortality studies

TY - JOUR

T1 - Breast cancer mortality in mammographic screening in Europe

T2 - a review of incidence-based mortality studies

AU - Njor, Sisse Helle

AU - Nyström, Lennarth

AU - Moss, Sue

AU - Paci, Eugenio

AU - Broeders, Mireille

AU - Segnan, Nereo

AU - Lynge, Elsebeth

AU - EUROSCREEN Working Group

PY - 2012/9

Y1 - 2012/9

N2 - Objectives To estimate the impact of service mammography screening on breast cancer mortality using European incidence-based mortality (IBM) studies (or refined mortality studies). IBM studies include only breast cancer deaths occurring in women with breast cancer diagnosed after their first invitation to screening. Methods We conducted a literature review and identified 20 publications based on IBM studies. They were classified according to the method used for estimating the expected breast cancer mortality in the absence of screening: (1) women not yet invited; (2) historical data from the same region as well as from historical and current data from a region without screening; and (3) historical comparison group combined with data for non-participants. Results The estimated effect of mammography screening on breast cancer mortality varied across studies. The relative risks were 0.76-0.81 in group 1; 0.75-0.90 in group 2; and 0.52-0.89 in group 3. Study databases overlapped in both Swedish and Finnish studies, adjustment for lead time was not optimal in all studies, and some studies had other methodological limitations. There was less variability in the relative risks after allowing for the methodological shortcomings. Conclusions Based on evidence from the most methodologically sound IBM studies, the most likely impact of European service mammography screening programmes was a breast cancer mortality reduction of 26% (95% confidence interval 13-36%) among women invited for screening and followed up for 6-11 years.

AB - Objectives To estimate the impact of service mammography screening on breast cancer mortality using European incidence-based mortality (IBM) studies (or refined mortality studies). IBM studies include only breast cancer deaths occurring in women with breast cancer diagnosed after their first invitation to screening. Methods We conducted a literature review and identified 20 publications based on IBM studies. They were classified according to the method used for estimating the expected breast cancer mortality in the absence of screening: (1) women not yet invited; (2) historical data from the same region as well as from historical and current data from a region without screening; and (3) historical comparison group combined with data for non-participants. Results The estimated effect of mammography screening on breast cancer mortality varied across studies. The relative risks were 0.76-0.81 in group 1; 0.75-0.90 in group 2; and 0.52-0.89 in group 3. Study databases overlapped in both Swedish and Finnish studies, adjustment for lead time was not optimal in all studies, and some studies had other methodological limitations. There was less variability in the relative risks after allowing for the methodological shortcomings. Conclusions Based on evidence from the most methodologically sound IBM studies, the most likely impact of European service mammography screening programmes was a breast cancer mortality reduction of 26% (95% confidence interval 13-36%) among women invited for screening and followed up for 6-11 years.

KW - Breast Neoplasms

KW - Early Detection of Cancer

KW - Europe

KW - Female

KW - Humans

KW - Incidence

KW - Mammography

KW - Mass Screening

U2 - 10.1258/jms.2012.012080

DO - 10.1258/jms.2012.012080

M3 - Journal article

C2 - 22972809

SN - 0969-1413

VL - 19 Suppl 1

SP - 33

EP - 41

JO - Journal of Medical Screening

JF - Journal of Medical Screening

ER -