In the Korean hereditary breast cancer (KOHBRA) study, the incidence of BRCA mutation was found to be 24.8% (106/428) in breast cancer patients with a family history of breast/ovarian cancers [6]; However, few studies have investigated breast cancer patients who carry germline mutations in both BRCA1 and BRCA2. This evidence concerns the gene BRCA1 and ovarian carcinoma.