Women who have severe menopausal symptoms after undergoing bilateral prophylactic salpingo-oophorectomy may consider using short-term menopausal hormone therapy after surgery to alleviate these symptoms. [The increase in breast cancer risk associated with certain types of menopausal hormone therapy is much less than the decrease in breast cancer risk associated with bilateral prophylactic salpingo-oophorectomy (20).]
What are the cancer risk reduction options for women who are at increased risk of breast cancer but not at the highest risk?
Risk-reducing surgery is not considered an appropriate cancer prevention option for women who are not at the highest risk of breast cancer (that is, for those who do not carry a high-penetrance gene mutation that is associated with breast cancer or who do not have a clinical or medical history that puts them at very high risk). However, some women who are not at very high risk of breast cancer but are, nonetheless, considered as being at increased risk of the disease may choose to use drugs to reduce their risk.
Health care providers use several types of tools, called risk assessment models, to estimate the risk of breast cancer for women who do not have a deleterious mutation in BRCA1, BRCA2, or another gene associated with breast cancer risk. One widely used tool is the Breast Cancer Risk Assessment Tool (BRCAT), a computer model that takes a number of factors into account in estimating the risks of breast cancer over the next 5 years and up to age 90 years (lifetime risk). Women who have an estimated 5-year risk of 1.67 percent or higher are classified as “high-risk,” which means that they have a higher than average risk of developing breast cancer. This high-risk cutoff (that is, an estimated 5-year risk of 1.67 percent or higher) is widely used in research studies and in clinical counseling.
Two drugs, tamoxifen and raloxifene, are approved by the U.S. Food and Drug Administration (FDA) to reduce the risk of breast cancer in women who have a 5-year risk of developing breast cancer of 1.67 percent or more (21-23). Tamoxifen is approved for risk reduction in both premenopausal and postmenopausal women, and raloxifene is approved for risk reduction in postmenopausal women only. In large randomized clinical trials, tamoxifen, taken for 5 years, reduced the risk of invasive breast cancer by about 50 percent in high-risk postmenopausal women (23); raloxifene, taken for 5 years, reduced breast cancer risk by about 38 percent in high-risk postmenopausal women (24). Both drugs block the activity of estrogen, thereby inhibiting the growth of some breast cancers. The US Preventive Services Task Force (USPSTF) recommends that women at increased risk of breast cancer talk with their health care professional about the potential benefits and harms of taking tamoxifen or raloxifene to reduce their risk (25).
Another drug, exemestane, was recently shown to reduce the incidence of breast cancer in postmenopausal women who are at increased risk of the disease by 65 percent (26). Exemestane belongs to a class of drugs called aromatase inhibitors, which block the production of estrogen by the body. It is not known, however, whether any of these drugs reduces the very high risk of breast cancer for women who carry a known mutation that is strongly associated with an increased risk of breast cancer, such as deleterious mutations in BRCA1 and BRCA2.
Some women who have undergone breast cancer surgery, regardless of their risk of recurrence, may be given drugs to reduce the likelihood that their breast cancer will recur. (This additional treatment is called adjuvant therapy.) Such treatment also reduces the already low risks of contralateral and second primary breast cancers. Drugs that are used as adjuvant therapy to reduce the risk of breast cancer after breast cancer surgery include tamoxifen, aromatase inhibitors, traditional chemotherapy agents, and trastuzumab.
What can women at very high risk do if they do not want to undergo risk-reducing surgery?
Some women who are at very high risk of breast cancer (or of contralateral breast cancer) may undergo more frequent breast cancer screening (also called enhanced screening). For example, they may have yearly mammograms and yearly magnetic resonance imaging (MRI) screening—with these tests staggered so that the breasts are imaged every 6 months—as well as clinical breast examinations performed regularly by a health care professional (27). Enhanced screening may increase the chance of detecting breast cancer at an early stage, when it may have a better chance of being treated successfully.
Women who carry mutations in some genes that increase their risk of breast cancer may be more likely to develop radiation-associated breast cancer than the general population because those genes are involved in the repair of DNA breaks, which can be caused by exposure to radiation. Women who are at high risk of breast cancer should ask their health care provider about the risks of diagnostic tests that involve radiation (mammograms or x-rays). Ongoing clinical trials are examining various aspects of enhanced screening for women who are at high risk of breast cancer.
Chemoprevention (the use of drugs or other agents to reduce cancer risk or delay its development) may be an option for some women who wish to avoid surgery. Tamoxifen and raloxifene have both been approved by the FDA to reduce the risk of breast cancer in women at increased risk (see Question 6). Whether these drugs can be used to prevent breast cancer in women at much higher risk, such as women with harmful mutations in BRCA1 or BRCA2 or other breast cancer susceptibility genes, is not yet clear, although tamoxifen may be able to help lower the risk of contralateral breast cancer among BRCA1 and BRCA2 mutation carriers previously diagnosed with breast cancer (28).
Does health insurance cover the cost of risk-reducing surgeries?
Many health insurance companies have official policies about whether and under what conditions they will pay for prophylactic mastectomy (bilateral or contralateral) and bilateral prophylactic salpingo-oophorectomy for breast and ovarian cancer risk reduction. However, the criteria used for considering these procedures as medically necessary may vary among insurance companies. Some insurance companies may require a second opinion or a letter of medical necessity from the health care provider before they will approve coverage of any surgical procedure. A woman who is considering prophylactic surgery to reduce her risk of breast and/or ovarian cancer should discuss insurance coverage issues with her doctor and insurance company before choosing to have the surgery.
The Women’s Health and Cancer Rights Act (WHCRA), enacted in 1999, requires most health plans that offer mastectomy coverage to also pay for breast reconstruction surgery after mastectomy. More information about WHCRA can be found through the Department of Labor.