Article Text
Abstract
Introduction Breast screening reduces mortality from breast cancer through early detection. Despite its benefits, breast cancer screening presents some adverse effects, as false positive (FP) results. Our aim was to estimate the risk of cancer detection associated to have experienced a previous FP mammography.
Methods The Cumulative False Positive Risk study includes eight population-based screening programs in Spain, between 1990 and 2006, that invites women aged between 45/50 and 69 years, with no previous breast cancer. We included women participating in at least two screenings rounds. A positive mammogram reading was considered a FP result if, after further assessments, breast cancer was not diagnosed. Cancer detection risk was estimated through OR with a multivariate discrete-time-hazard model with a random intercept. The model included adjusting variables related to screening programs (radiologic unit, reading method and number of projections) and woman (age, hormone replacement therapy use, menopausal status, previous invasive procedures and familial history of breast cancer).
Results Women who had experienced at least one previous FP result had a higher cancer detection rate than those without a FP (4.72 per 1000 mammograms vs 2.56 per 1000 mammograms). The adjusted OR of cancer detection was higher in women with a FP in any previous screening (OR=1.88 95% CI 1.76 to 2.00).
Conclusion Women with a previous FP result had a higher risk of cancer detection. This result may suggest that factors related to FP could provide useful information to redesign different early detection strategies for specific subgroups of women.