Mammographic screening for breast cancer: few new data

(1) A new comparative randomised trial of mammographic screening for breast cancer, involving about 160 000 women aged from 39 to 49, followed for more than 10 years, showed no significant reduction in breast cancer mortality. After seven screening mammograms, 23% of the women had at least one false-positive result. (2) The results of the Swedish Two-County trial were challenged after re-examination of cancer registries. (3) One study showed that nearly 25% of women in whom breast cancer was detected with mammography in the Malmo-1 study would otherwise have remained asymptomatic for 25 years. (4) An update of the Cochrane meta-analysis confirmed previous conclusions: no tangible benefits were found in the 3 most reliable trials. When 5 less reliable trials were also taken into account, screening was found to reduce breast cancer mortality after 13 years of follow-up. (5) In France, there are no data on the impact of screening on the frequency of surgery or chemotherapy, the detection of harmless tumours or carcinoma in situ, or the risk of over-diagnosis. (6) In practice, healthcare professionals must inform their patients of the uncertainties concerning mammographic screening.