The risks associated with mutations in BRCA-1 and BRCA-2 include a 50 percent to 85 percent risk for developing breast cancer and a 10 percent to 45 percent risk for developing ovarian cancer. These risks are significantly increased over the risks for these cancers in the general population.
Information is limited on how other non-genetic factors influence the risks associated with these mutations. For people who have a BRCA mutation, clinical management choices may include increased or more intensive monitoring, chemoprevention, or prophylactic surgery to remove at-risk organs. Screening must be started at a young age, usually between the ages of 20-25 years of age.
Although some of these options may reduce the risk for developing breast and / or ovarian cancer, no option totally eliminates this risk.
Although the BRCA genes are the most common hereditary causes of breast and ovarian cancer, there are several additional genes that may also contribute to a family history of breast, ovarian or other cancers. Testing for these genes recently became available.