Prevalence and Characterization BRCA2 in Male Breast Cancer Cases

摘要

Male breast cancer (MBC) is rare, with an incidence rate of 0.5-1/100,000 peryear. It has a significant familial component and is observed in combination with female breast cancer in BRCA2 kindreds, while it is rarely observed in BRCA1 kindreds. The objective of this grant is to study a series of unselected population-based MBC cases and their relatives to characterize the role of BRCA2 in MBC and to estimate the attributable risk of MBC due to BRCA2 mutations. At the end of one year, we have collected family history data and DNA samples on 78 MBC cases and paraffin-embedded tissue on 16 of those. of the 78 MBC cases, 41(53%) have a family history of breast cancer in a first or second degree relative. Sixty six MBC cases have been screened for mutations in 38 of the 79 BRCA2 amplicons. Three predisposing, truncating mutations, one missense mutation of unknown significance, and one polymorphism have been identified. The missense mutation had been identified previously in an early-onset breast cancer family which we have studied. The polymorphism occurs with a frequency of 24% and will be useful in constructing the haplotypes of these MBC cases.