Etiology and Clinical Features of Hereditary Breast and Ovarian Cancer (HBOC)

The genetic basis of HBOC is a germline (inherited) mutation in either the BRCA1 or BRCA2 genes. Normally, the proteins produced by the BRCA1 and BRCA2 genes prevent cells from becoming malignant by aiding in the repair of mutations in other genes through a process known as double-stranded DNA repair. Therefore, an inherited mutation in either of these genes, also known as tumor suppressor genes, greatly increases the probability of malignant transformation and cancer. Approximately 7% of breast cancer and 11 – 15% of ovarian cancer cases are caused by BRCA1 or BRCA2, which are inherited in an autosomal dominant pattern.1,2,3 When assessing hereditary cancer risk, a patient’s personal and family history is collected to investigate the risk for HBOC. Once a patient is identified as being at increased risk of HBOC, genetic test results provide the most accurate means of cancer risk assessment for a patient.