Preventive Surgery to Reduce Breast Cancer Risk

For some women who have a very high risk of breast cancer, preventive surgery to remove the breasts (prophylactic mastectomy) may be an option to lower their risk.

Should I consider surgery to lower my risk of breast cancer?

You might consider preventive surgery if you:

  • Have a mutation in the BRCA1 or BRCA2 gene (or certain other genes that increase breast cancer risk) that is found by genetic testing
  • Have a strong family history of breast cancer (such as breast cancer in several close relatives, or breast cancer in at least one relative at a young age)
  • Had radiation therapy to the chest before age 30
  • Have (or have had) cancer in one breast (especially if you also have a strong family history)

Like any type of surgery, a mastectomy can have risks and side effects, some of which could affect your quality of life. Because of this, preventive surgery is not usually a good option for women who are at average risk of breast cancer, or for those who are at only slightly increased risk.

For women who are known (or strongly suspected) to have a BRCA1 or BRCA2 gene mutation, a prophylactic oophorectomy (removal of the ovaries) might be recommended as well.

Prophylactic mastectomy

A prophylactic mastectomy is surgery to remove one or both breasts to lower the chances of getting breast cancer. While a prophylactic mastectomy can lower this risk by 90% or more, it doesn’t guarantee that you will not get breast cancer. This is because it's not possible to remove all breast cells, even with a mastectomy. The breast cells that are left behind might still go on to become cancer.

There are two main situations in which a prophylactic mastectomy might be considered.

For women at very high risk of breast cancer

For women in this group, removing both breasts (known as a bilateral prophylactic mastectomy) before cancer is diagnosed can greatly reduce (but not eliminate) the risk of getting breast cancer. 

Unfortunately there’s no way to know for sure ahead of time if a woman will benefit from this surgery. For example, most women with a BRCA1 or BRCA2 gene mutation will develop breast cancer at some point. Having a prophylactic mastectomy before the cancer occurs might add many years to their lives. But not all women with BRCA1 or BRCA2 mutations develop breast cancer. For some women the surgery might not have been helpful. Although they might still get some important benefits from the surgery such as peace of mind, they would also have to deal with its aftereffects.

For women already diagnosed with breast cancer

Some women who have already been diagnosed with breast cancer choose to have the other breast removed at the time of the surgery to remove the breast with cancer. This operation (known as a contralateral prophylactic mastectomy, or CPM) can help lower their risk of developing a second breast cancer. 

This is more likely to be a good option for women who also have other factors that increase their risk of getting another breast cancer, such as a BRCA1 or BRCA2 mutation or a strong family history of breast cancer.

But for women without a family history of breast cancer or other risk factors, the benefit of a CPM is less clear. Having breast cancer does raise your risk of getting cancer in the other breast, but this risk is still usually low, and many women overestimate this risk. And while CPM lowers the risk of getting cancer in the other breast, for most women it does not increase the chances of living longer.  

Before having this type of surgery, it’s very important to talk with your health care provider so that you understand how much it's likely to benefit you, versus the likelihood of risks and side effects. You might also want to get a second medical opinion, as well as talk to other women who have had this surgery, before deciding if it’s right for you.

Prophylactic oophorectomy (removal of the ovaries)

Women with a BRCA1 or BRCA2 mutation have a high risk of developing both breast cancer and ovarian cancer. 

Most doctors recommend that women with a BRCA1 or BRCA2 mutation have surgery to remove their ovaries (and usually the attached fallopian tubes as well) once they’ve finished having children. This operation, known as a prophylactic oophorectomy, greatly reduces the risk of ovarian cancer. Some studies have suggested it can lower the risk of breast cancer as well, although some recent studies have called this into question. Some women choose to have this surgery done along with a prophylactic mastectomy.

Removing the ovaries causes a woman to go into menopause. This can lead to symptoms such as hot flashes, trouble sleeping, vaginal dryness, loss of bone density, and anxiety or depression. 

Again, it’s important to talk to your health care provider so that you’re well informed about the possible benefits, risks, and side effects of this type of surgery. You might also want to talk to other women who have had this surgery before deciding if it’s right for you.

Other options to reduce breast cancer risk

If you’re concerned about your breast cancer risk, talk to your health care provider. They can help you estimate your risk based on your age, family history, and other factors. If you are at increased risk, you might consider taking medicines that can help lower your risk. Your health care provider might also suggest you have more intensive screening for breast cancer, which might include starting screening at an earlier age or having other tests in addition to mammography.

There are also other things that all women can do to help lower their risk of breast cancer, such as being active, staying at a healthy weight, and limit or avoiding alcohol. For more information, see Can I Lower My Risk of Breast Cancer?

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

American Cancer Society. Breast Cancer Facts & Figures 2019-2020. Atlanta, Ga: American Cancer Society; 2019.

Guillem JG, Wood WC, Moley JF, et al. ASCO/SSO review of current role of risk-reducing surgery in common hereditary cancer syndromes. J Clin Oncol. 2006; 24:4642-4660.

Heemskerk-Gerritsen BA, Seynaeve C, van Asperen CJ, et al. Breast cancer risk after salpingo-oophorectomy in healthy BRCA1/2 mutation carriers: Revisiting the evidence for risk reduction. J Natl Cancer Inst. 2015;107(5).

King TA, Sakr R, Patil S, et al. Clinical management factors contribute to the decision for contralateral prophylactic mastectomy. J Clin Oncol. 2011; 29:2158-2164.

Kotsopoulos J, Huzarski T, Gronwald J, et al. Bilateral oophorectomy and breast cancer risk in BRCA1 and BRCA2 mutation carriers. J Natl Cancer Inst. 2017;109(1).

Kurian AW, Lichtensztajn DY, Keegan TH, et al. Use of and mortality after bilateral mastectomy compared with other surgical treatments for breast cancer in California, 1998-2011. JAMA. 2014;312(9):902-914.

National Cancer Institute. Surgery to Reduce the Risk of Breast Cancer. Accessed at on August 1, 2019.

National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Breast Cancer Risk Reduction. V.1.2019. Accessed at on August 1, 2019.

Pesce C, Liederbach E, Wang C, et al. Contralateral prophylactic mastectomy provides no survival benefit in young women with estrogen receptor-negative breast cancer. Ann Surg Oncol. 2014;21(10):3231-3239.

Rebbeck TR, Lynch HT, Neuhausen SL, et al. Prophylactic oophorectomy in carriers of BRCA1 or BRCA2 mutations. N Engl J Med. 2002;346:1616–1622.

Terry MB, Daly MB, Phillips KA, et al. Risk-reducing oophorectomy and breast cancer risk across the spectrum of familial risk. J Natl Cancer Inst. 2019;111(3):331-334.

Wong SM, Freedman RA, Sagara Y, et al. Growing use of contralateral prophylactic mastectomy despite no improvement in long-term survival for invasive breast cancer. Ann Surg. 2017;265(3):581-589. 


Last Medical Review: September 10, 2019 Last Revised: September 10, 2019

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