Prophylactic mastectomy: Surgery to lower breast cancer risk

If you have a high risk of breast cancer, one option to lower risk may be surgery to remove your breasts. If you're considering this preventive surgery, here's some information to help you get ready to talk about it with your healthcare professional.

Prophylactic mastectomy is surgery to remove one or both breasts to lower the risk of breast cancer. It includes these procedures:

• Bilateral prophylactic mastectomy removes the tissue from both breasts in someone who hasn't been diagnosed with breast cancer. This greatly lowers the risk of breast cancer in both breasts.
• Contralateral prophylactic mastectomy removes the healthy breast in someone who has breast cancer in one breast. Removing the healthy breast greatly lowers the risk that cancer will happen in that breast. Contralateral prophylactic mastectomy to remove the healthy breast is typically done at the same time as a mastectomy to remove the breast with cancer.

Prophylactic mastectomy also is called a risk-reducing mastectomy. Other names people might use for this procedure include double mastectomy, preventive mastectomy or preventative mastectomy.

Prophylactic mastectomy is an option for women with a high risk of breast cancer. You may qualify for this preventive surgery if you have:

• A strong family history of breast cancer. If you've never had breast cancer but you have a strong family history, surgery to remove both breasts may be an option. A strong family history means having a mother, sister or daughter who has had breast cancer, especially before age 50. A strong family history also may mean that you have multiple family members — on your mother's side or father's side— with breast or ovarian cancer.
• Positive results from genetic testing. If you've never had breast cancer but genetic testing finds DNA changes that greatly raise your risk of breast cancer, surgery to remove both breasts may be an option. DNA changes, also called variants or mutations, that increase breast cancer risk include BRCA1, BRCA2 and others. These changes are more common in families with multiple generations affected by breast cancer at a young age and in families of Ashkenazi Jewish descent.
• A history of radiation therapy to the chest. If you've never had breast cancer but you had radiation therapy to your chest between the ages of 10 and 30, surgery to remove both breasts may be an option.
• Already had cancer in one breast. In those with breast cancer who are having a mastectomy to remove the cancer, surgery to also remove the healthy breast may be an option. You might consider this option if you have a high risk of developing breast cancer in the healthy breast. Having a high risk means that you have an inherited DNA change, such as BRCA1 or BRCA2, a strong family history of breast cancer, or had radiation therapy to your chest as a child or young adult.

To figure out your risk of cancer, your healthcare professional may do a breast cancer risk assessment. This often involves asking questions about your health history and your family history of cancer. The healthcare professional also may want to know about the results of any genetic tests you've had and whether you've ever had a breast biopsy.

The age you should consider having a prophylactic mastectomy depends on several factors. It may depend on which inherited DNA changes run in your family, your family history of breast cancer and the age at which family members were diagnosed with cancer. It also may depend on other risk factors, such as a personal history of breast changes that increase the risk of breast cancer. The age at which you may get the most benefit will depend on your situation. Talk with your healthcare professional about your personal risk of breast cancer and your preferences.

Prophylactic mastectomy doesn't lower the risk of breast cancer to zero. Even with this preventive surgery, there is still a small chance of breast cancer. This is because mastectomy typically doesn't remove all of the breast tissue and breast skin. The tiny amount of breast tissue that remains could still develop breast cancer, though the chances are very low.

Prophylactic mastectomy significantly lowers the risk of breast cancer. Studies have found these results for risk-reducing surgery:

• If you have never had breast cancer but have a high risk: Bilateral prophylactic mastectomy removes both breasts and lowers the risk of cancer in either breast by 90 percent or more.
• If you've had breast cancer in one breast and also have a high risk: Contralateral prophylactic mastectomy removes the healthy breast and lowers the risk of cancer in that breast by up to 95 percent. It also may improve overall survival, though exactly how much depends on your age at the time of your breast cancer diagnosis.
• If you've had cancer in one breast, but don't have a high risk: Contralateral prophylactic mastectomy removes the healthy breast and lowers the risk of cancer in that breast. But the risk of getting cancer in your other breast is very low. Removing your healthy breast has little or no effect on overall survival.

Talk with your healthcare professional about your risk of breast cancer. The health professional can help you understand how a prophylactic mastectomy may affect your personal risk of cancer.

Benefits of prophylactic mastectomy:

• Lowers the risk of breast cancer significantly.
• Improves overall survival in those who have a high risk of breast cancer.
• Avoids the side effects of medicines that reduce breast cancer risk.
• Reduces need for some breast cancer screening tests, such as mammograms and breast MRIs. Breast exams by a healthcare professional typically continue.
• Reduces the worry that may come with knowing you have a high risk of breast cancer.

Risks and complications of prophylactic mastectomy:

• Carries a risk of complications after surgery, such as pain, infection and swelling as you heal. For most, these go away with time. For some, pain may last a long time.
• May require more than one surgery to complete reconstruction, fix complications or achieve the cosmetic outcome you want.
• Often causes loss of sensation in the breast and nipple.
• Removes the ability to breastfeed.
• Sometimes changes how you feel about your body and your appearance.

Some people wonder if a prophylactic mastectomy may cause lymphedema. This is swelling that can happen when the lymphatic system is damaged by surgery, such as when surgeons remove lymph nodes in the arm pit during a mastectomy. Surgeons typically don't remove these lymph nodes during a prophylactic mastectomy. So the arm swelling that can happen with lymphedema is less likely with prophylactic mastectomy.

Mastectomy options include:

• Total mastectomy. Also called simple mastectomy, this surgery removes most of the breast tissue, as well as the skin and nipple.
• Skin-sparing mastectomy. This surgery removes most of the breast tissue and the nipple but leaves the skin.
• Nipple-sparing mastectomy. This surgery removes most of the breast tissue but leaves the skin and the nipple.

Skin-sparing and nipple-sparing mastectomies leave more breast tissue behind than a total mastectomy does. In theory, this tissue could develop cancer in the future, but the risk is very small. Studies show skin-sparing and nipple-sparing procedures are safe for those with a high risk of breast cancer.

Most people having a prophylactic mastectomy choose to have breast reconstruction surgery to restore shape to the breasts. Some people choose to have a flat chest after surgery.

Reconstruction options include:

• Breast reconstruction to create new breasts using implants.
• Breast reconstruction to create new breasts using your own tissue.
• Chest wall reconstruction to create a smooth, flat appearance of the chest, also called aesthetic flat closure.

Immediate reconstruction is when the reconstruction surgery happens at the same time as the surgery to remove the breasts. It may be an option for those having reconstruction with implants. Once the surgeon finishes removing the breast tissue, a plastic or reconstructive surgeon places the breast implants. Whether this is an option for you may depend on your body and the type of reconstruction you're having.

Delayed reconstruction is when the reconstruction starts at the time of the mastectomy but is finished in another procedure that happens later. Doing the reconstruction in stages may be necessary if you're having a contralateral prophylactic mastectomy and will have more treatments for your breast cancer.

Whether the reconstruction is immediate or delayed, many women need multiple operations to complete the reconstruction or fix complications.

Estrogen is a hormone the body makes that can fuel breast cancer development and growth. Most breast cancers use hormones to help them grow. Preventive medicines that block the effects of estrogen or reduce estrogen may lower the risk of breast cancer. Which medicines your healthcare team recommends may depend on whether you have been through menopause. The recommendations also may depend on your medical and surgical history.

Other options may include:

• Surgery to remove the ovaries. A prophylactic oophorectomy removes the ovaries. When this surgery is done before menopause, it lowers the risk of both breast cancer and ovarian cancer.
• Breast cancer screening. If you have a high risk of breast cancer, your healthcare professional may suggest having breast MRIs in addition to mammograms to screen for breast cancer. Screening also may involve regular breast exams by your healthcare professional and breast self-exams for breast awareness.
• Healthy lifestyle choices. Keeping a weight that is healthy for you, choosing a healthy diet, exercising most days of the week, avoiding alcohol and using caution with hormone therapy for menopause symptoms may help lower the risk of breast cancer.

Yes, some people regret having a prophylactic mastectomy. But studies find that the great majority of women do not regret having this risk-reducing surgery. This is especially true for those who are very worried about their risk of cancer. For these women, the surgery may bring relief from that worry.

Still, some do have regrets about choosing to have this preventive surgery. Regrets are more likely if complications happen during or after surgery.

Deciding what to do with the knowledge that you are at high risk of breast cancer can be a complex and time-consuming process. You may find it's helpful to work with a team of healthcare professionals that includes a genetic counselor to get a complete evaluation of your risk. Take the time you need to understand all of your options.

Many breast centers are staffed with breast medicine specialists, genetic counselors, breast surgeons and reconstructive surgeons. They can explain your options and help you weigh the benefits and risks of each one. Consider seeking a second opinion.

It also may help to talk with others who have faced the same decision. Ask your healthcare professional about support groups in your area. Find support online through Mayo Clinic Connect, a community where you can connect with others for support, practical information and answers to everyday questions.

Making the decision whether to have prophylactic mastectomy is not urgent. Give yourself time to weigh all the pros and cons.