BRCA Genetic Testing for Patients With and Without Breast Cancer

Of the more than 200,000 breast cancers diagnosed annually in the United States, 5-10% are associated with obvious hereditary predisposition, which is mostly related to autosomal dominant mutations of the BRCA1 and BRCA2 genes. BRCA1/2 mutations confer an increased lifetime risk for the development of breast cancer (up to 80%), contralateral breast cancer (about 30% at 10 years), ovarian cancer (up to 40% for BRCA1 and 20% for BRCA2), and other cancers. BRCA mutations are rare in the general population, occurring in 1 per 400-800 individuals, but high-risk populations exist and include persons with the following: