Can Breast Cancer Be Prevented?

From the American Cancer Society

There is no sure way to prevent breast cancer. But there are things all women can do that might reduce their risk and help increase the odds that if cancer does occur, it is found at an early, more treatable stage.

Lowering your risk: You can lower your risk of breast cancer by changing those risk factors that can be changed. If you limit alcohol use, exercise regularly, and keep a healthy weight, you are decreasing your risk of getting breast cancer. Women who choose to breast-feed for at least several months may also reduce their breast cancer risk.

Not using post-menopausal hormone therapy (PHT) if you don't need it can also help you avoid raising your risk.

Finding breast cancer early: It is also important for women to follow the American Cancer Society's guidelines for finding breast cancer early. (See the section, "How is breast cancer found?")

For women who are or may be at increased risk

If you have a higher risk for breast cancer there may be some things you can do to reduce your chances of getting breast cancer. Before deciding which, if any, of these may be right for you, talk with your doctor.

Genetic testing: There are tests that can tell if a woman has certain changed (mutated) genes linked to breast cancer. With this information, women can then take steps to reduce their risk. Recently the U.S. Preventive Services Task Force made recommendations for genetic testing. They suggest that only women with a strong family history be evaluated for genetic testing for BRCA mutations. This group is only about 2% of adult women in the United States.

If you are thinking about genetic testing, you should talk to a genetic counselor, nurse, or doctor qualified to explain the results of these tests. It is very important that you know what genetic testing can and can't tell you, and to carefully weigh the benefits and risks of testing before these tests are done. Testing is expensive and may not be covered by some health insurance plans. For more information, see our document, Genetic Testing: What You Need to Know.

Breast cancer chemoprevention: Chemoprevention is the use of drugs to reduce the risk of cancer. Many drugs have been studied for use in lowering breast cancer risk. The drug tamoxifen has already been used for many years as a treatment for some types of breast cancer. Studies have shown that women at high risk for breast cancer are less likely to get the disease if they take tamoxifen. Another drug, raloxifene, has been approved to help reduce breast cancer risk in women past menopause who are at high risk for breast cancer. Other drugs are also being studied.

Preventive surgery for women with very high breast cancer risk: For the few women who have a very high risk for breast cancer, preventive surgery such as bilateral (double) mastectomy may be an option.

Preventive (prophylactic) double (bilateral) mastectomy: For some who are at very high risk for breast cancer, this surgery (a double mastectomy) may be an option. In this operation both breasts are removed before there is any known breast cancer. While this operation removes nearly all of the breast tissue, a small amount remains. So although this operation greatly reduces the risk of breast cancer, the disease can still start in the breast tissue that remains after surgery. To date, this has been a rare problem.

The reasons for thinking about this type of surgery need to be very strong. There is no way to know ahead of time whether this surgery will benefit a particular woman. A second opinion is strongly recommended before making a decision to have this type of surgery.

Preventive ovary removal (prophylactic oophorectomy): Women with a certain gene change (BRCA mutation) who have their ovaries removed may reduce their risk of breast cancer by half or more. This is because taking out the ovaries removes the main sources of estrogen in the body.

Although this document is not about ovarian cancer, it is important that women with this gene change also know that they also have a high risk of getting ovarian cancer. Most doctors recommend that these women have their ovaries removed after they are done having children.