Currently, there are no proven means to prevent breast cancer, although there are ways to reduce the risk of breast cancer in some women.

• For women with especially strong family histories of breast cancer (such as BRCA mutations), a prophylactic mastectomy (preventive removal of the breasts) may be considered. This appears to reduce the risk of developing breast cancer by at least 95%.
  
   
• Women who are at higher than normal risk for developing breast cancer may consider chemoprevention (the use of drugs to reduce breast cancer risk). One such drug is tamoxifen (Nolvadex), which is a selective estrogen receptor modulator (SERM). A SERM is a medication that blocks estrogen receptors in some tissues and not others. Tamoxifen can reduce a woman’s risk of developing breast cancer and the risk of the cancer recurring once a woman has been treated for breast cancer. Like estrogen, tamoxifen helps increase bone density in postmenopausal women and protects the cardiovascular system. Unlike estrogen, SERMs do not promote the development of breast cells into cancer cells; however, they may increase the risk of blood clots and uterine (endometrial) cancer.

For most women, regular mammography and clinical breast examinations (examinations by a doctor or other health-care professional) can help find early signs of breast cancer. In addition, women should become familiar with their own breasts. Checking your own breasts for lumps with breast self-examination may help if performed correctly. Talk with your doctor for more information.

Screening guidelines

The U.S. Preventive Services Task Force (USPSTF) recommends that women 40 to 75 years old undergo mammography every one to two years, and the American Cancer Society (ACS) recommends yearly mammography. Mammography is the best tool doctors have to screen for breast cancer and can detect a tumor that is too small to be felt. All women should talk with their doctors about mammography and decide on an appropriate screening schedule.

Occasionally, mammograms may miss a cancer. Other methods of breast imaging, such as ultrasound and magnetic resonance imaging (MRI), are not regularly used for screening purposes. However, they may be helpful for evaluating women at a higher risk for breast cancer, including women with a BRCA mutation and women who received radiation therapy for Hodgkin lymphoma. These other screening methods may also be used for those with a suspicious finding on physical examination. If there are suspicious findings on physical examination, further evaluation is necessary, even if the mammogram is interpreted as normal.

The USPSTF and ACS differ on their recommendations for clinical breast examination. The USPSTF recommends a clinical breast examination along with mammography, and the ACS recommends a clinical breast examination every one to three years. Breast self-examination has not been shown to lower deaths from breast cancer, but it is important for women to become familiar with their breasts so that they can be aware of any changes. Women are encouraged to discuss the frequency of screening with their doctors.