Breast Cancer after Prophylactic Bilateral Mastectomy in Women with a BRCA1 or BRCA2 Mutation Hanne Meijers-Heijboer, M.D., Bert van Geel, M.D., Ph.D., Wim L.J. van Putten, M.Sc., Sonja C. Henzen-Logmans, M.D., Ph.D., Caroline Seynaeve, M.D., Ph.D., Marian B.E. Menke-Pluymers, M.D., Ph.D., Carina C.M. Bartels, M.D., Leon C. Verhoog, M.D., Ans M.W. van den Ouweland, Ph.D., Martinus F. Niermeijer, M.D., Ph.D., Cecile T.M. Brekelmans, M.D., Ph.D., and Jan G.M. Klijn, M.D., Ph.D. ABSTRACT Background Women with a BRCA1 or BRCA2 mutation have a high risk of breast cancer and may choose to undergo prophylactic bilateral total mastectomy. We investigated the efficacy of this procedure in such women. Methods We conducted a prospective study of 139 women with a pathogenic BRCA1 or BRCA2 mutation who were enrolled in a breast-cancer surveillance program at the Rotterdam Family Cancer Clinic. At the time of enrollment, none of the women had a history of breast cancer. Seventy-six of these women eventually underwent prophylactic mastectomy, and the other 63 remained under regular surveillance. The effect of mastectomy on the incidence of breast cancer was analyzed by the Cox proportional-hazards method in which mastectomy was modeled as a time-dependent covariate. Results No cases of breast cancer were observed after prophylactic mastectomy after a mean (±SE) follow-up of 2.9±1.4 years, whereas eight breast cancers developed in women under regular surveillance after a mean follow-up of 3.0±1.5 years (P=0.003; hazard ratio, 0; 95 percent confidence interval, 0 to 0.36). The actuarial mean five-year incidence of breast cancer among all women in the surveillance group was 17±7 percent. On the basis of an exponential model, the yearly incidence of breast cancer in this group was 2.5 percent. The observed number of breast cancers in the surveillance group was consistent with the expected number (ratio of observed to expected cases, 1.2; 95 percent confidence interval, 0.4 to 3.7; P=0.80). Conclusions In women with a BRCA1 or BRCA2 mutation, prophylactic bilateral total mastectomy reduces the incidence of breast cancer at three years of follow-up. Source InformationFrom the Departments of Medical Oncology (H.M.-H., C.S., L.C.V., C.T.M.B., J.G.M.K.), Surgery (B.G., M.B.E.M.-P., C.C.M.B.), Statistics (W.L.J.P.), Clinical Genetics (H.M.-H., A.M.W.O., M.F.N.), and Pathology (S.C.H.-L.), Erasmus University Medical Center, Rotterdam, the Netherlands. Address reprint requests to Dr. Klijn at the Rotterdam Family Cancer Clinic, Department of Medical Oncology, Dr. Daniel den Hoed Kliniek, Erasmus University Medical Center Rotterdam, Groene Hilledijk 301, 3075 EA Rotterdam, the Netherlands, or at bos@onch.azr.nl. New England J of Medicine, Volume 345:159-164 July 19, 2001 Number 3 JNCI, 10/02 J Clin Oncol, 1/03 Lancet, 1/03 JNCI, 7/02/03 Cancer, 11/03 Abstract #C190 Frontiers in Cancer Prevention Res, 2003 JCO, 10/03 JCO, 3/04 Abstract #6041 ASCO, 2004 Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.