Breast Cancer

Prophylactic Mastectomy

A prophylactic mastectomy (also called a preventive or risk-reduction mastectomy) involves removing one or both breasts that have no sign of cancer to reduce the risk of developing breast cancer in the future. This procedure is generally reserved for women who are at high risk for developing a first or second breast cancer.

Physicians can help patients assess the risk of breast cancer. Being identified as high-risk does not mean a patient will definitely get cancer. Family history, genetic factors, anxiety about future cancer and body symmetry are common reasons for a woman to consider a prophylactic mastectomy.

Family history. A significant family history of breast cancer (for example, a mother, a sister or a daughter with the disease) may be a reason to have a prophylactic mastectomy. It is important to note, however, that 85 percent of breast cancers occur in women with no prior family history of the disease.

Genetic factors. Genetic testing can identify people who have an abnormal breast cancer gene (BRCA1 or BRCA2) associated with an inherited type of breast cancer. Patients with a strong family history of breast cancer or other cancers (such as ovarian, colon or prostate cancer) should discuss genetic testing with their health care provider. Mayo Clinic offers a full range of genetic testing and counseling.

Reduced anxiety. If a patient has had one breast removed because cancer was present, a prophylactic mastectomy may reduce her anxiety about cancer developing in the unaffected breast.

Symmetry. Some women who have a mastectomy choose to have the unaffected breast removed as well to give their body a more even appearance.

Prophylactic mastectomy and any subsequent breast reconstruction are major surgical procedures with lasting effects on body appearance. Although this procedure may reduce the risk of breast cancer, it does not guarantee that the patient will not develop cancer, and there is no evidence that it improves survival rates after a diagnosis of breast cancer. Breast tissue is widely distributed on the chest wall and also can be found in the armpit, above the collarbone or as low as the abdomen. No mastectomy can guarantee that all of the breast tissue will be removed, and any remaining tissue can still develop breast cancer.