Germline Findings from Genetic Testing for Breast Cancer

Five to 10 percent of breast cancers are hereditary tumors caused by pathogenic germline mutations in a responsible gene. Hereditary breast and ovarian cancer (HBOC), caused by loss-of-function germline mutation of tumor suppressor genes BRCA1 and BRCA2 (BRCA1/2), is the best known, but many other causative genes of hereditary breast cancer are also recognized. Accurate diagnosis of hereditary cancer not only provides patients with more appropriate surveillance and treatment options but also allows for early intervention in relatives at the same risk.