Breast cancer screening in women over age 50. A critical appraisal.

Breast cancer screening with mammography is strongly advocated by some and rejected by others. Discussions in the medical literature focus on the beneficial and unfavourable effects of breast cancer screening. Among the latter are the suggested excess mortality rate of screen-detected breast cancer patients, the high number of unnecessary biopsies, the possibility of overdiagnosis and subsequent unnecessary treatment, and the occurrence of interval breast cancer cases. It is concluded that screening can to a certain extent prevent women from dying of breast cancer but some negative effects are unavoidable. However, adequate training of the screening team can minimize the number of unnecessary biopsies and the occurrence of interval cancers. Research is needed to evaluate the natural course of so-called 'minimal' lesions, and to optimize screening tests. The search for new (imaging) techniques is needed to detect lobular cancers in dense breasts.