Prevalence and Characterization of BRCA2 in Male Breast Cancer Cases

Male breast cancer is rare, with an incidence rate of 0.5-1100,000 per year. The objective of this grant is to study male breast cancer cases to estimate the attributable risk of male breast cancer due to BRCA2 mutations. 170 Caucasian male breast cancer cases are participating, with age at diagnosis ranging from 28-93 years. Of the 166 cases with family history data, 49 have a family history of breast cancer in at least one first- or second- degree relative. Screening for BRCA2 mutations has been completed for 123 cases. Eleven deleterious mutations were identified in 17 cases, including 6 cases with the common 6174delT mutation. Based on mutations known to be deleterious, the prevalence of BRCA2 in male breast cancer is 13.8 17123 for both population- and clinic-based samples. When only considering population-based samples, the prevalence is 8.5 894. Accounting for the sensitivity of SSCA of approximately 80, the prevalence of BRCA2 is 10.6 89410.80 for population-based samples only and 17.2 for all screened samples. Family history is not a good predictor of BRCA2 mutation status. BRCA2 mutations appear to be more prevalent in unselected male cases than in unselected female breast cancer cases.