Breast cancer screening programmes--results of studies in foreign countries--situation in Belgium.

Results of randomized trials and case-control studies on breast cancer screening are reviewed. A combined analysis of data from the randomized studies indicates that a mortality reduction (29%) can be achieved by mammographic screening in women. Regular breast cancer screening by mammography for women aged 50-69 years reduces breast cancer mortality by 40% (confidence interval [CI] 95% about 27-55) in women who are screened at least once. In younger women, the results are inconclusive. The programme Europe against Cancer has recommended the setting-up of a network of pilot studies on breast cancer screening by mammography in the European Community in order to obtain the necessary experience, with a view to implementation of a national screening programme before the year 2000. In the Brussels project, the main objective is to develop a programme of quality assurance. In Belgium, there are other projects with different designs, for which the results are not yet available.