Preventive Surgery to Reduce Breast Cancer Risk

For the few women who have a very high risk for breast cancer, surgery to remove the breasts or ovaries may be an option.

Preventive (prophylactic) mastectomies: Removing both breasts before cancer is diagnosed can greatly reduce the risk of breast cancer (by up to 97%). Some women diagnosed with cancer in one breast choose to have the other, healthy breast removed as well to help prevent a second breast cancer. Breast removal does not completely prevent breast cancer because even a very careful surgeon will leave behind at least some breast cells, which might go on to become cancer.

Some of the reasons for considering this type of surgery may include:

  • Mutated BRCA genes found by genetic testing
  • Strong family history (such as breast cancer in several close relatives)
  • Lobular carcinoma in situ (LCIS) seen on biopsy
  • Previous cancer in one breast (especially in someone with a strong family history)

This type of surgery has been shown to be helpful in studies of large groups of women with certain conditions, but there’s no way to know ahead of time if this surgery will benefit any one woman. Some women with BRCA mutations will develop breast cancer early in life, and have a very high risk of getting a second breast cancer. A prophylactic mastectomy before the cancer occurs might add many years to their lives. But while most women with BRCA mutations develop breast cancer, some don’t. These women would not benefit from the surgery, but they would still have to deal with its aftereffects. Second opinions are strongly recommended before any woman decides to have this surgery.

Prophylactic oophorectomy (removal of the ovaries): Women with a BRCA mutation may reduce their risk of breast cancer by 50% or more by having their ovaries surgically removed before menopause. This is probably because the ovaries are the main sources of estrogen in the body.

It’s important that women with a BRCA mutation recognize they also have a high risk of developing ovarian cancer. Most doctors recommend that women with BRCA mutations have their ovaries surgically removed once they finish having children to lower this risk.

The American Cancer Society medical and editorial content team
Our team is made up of doctors and master’s-prepared nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Medical Review: June 1, 2016 Last Revised: August 18, 2016

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