Breast cancer risk reduction and risk assessment are active areas of research. Some studies are looking at methods of reducing risk for women at higher risk of breast cancer, such as new risk-lowering drugs. Other studies focus on new and better ways of knowing which women are at higher risk.
Some drugs used to treat breast cancer are under study for their use in risk reduction for women at higher risk. New drugs are also being developed.
Learn about FDA-approved drugs for lowering the risk of breast cancer.
Aromatase inhibitors are hormone drugs that are used to treat estrogen receptor-positive breast cancer in postmenopausal women (learn more). There are three aromatase inhibitors that are FDA-approved for the treatment of breast cancer in the U.S.: anastrozole (Arimidex), letrozole (Femara) and exemestane (Aromasin). They appear to be equally effective in treating breast cancer.
Aromatase inhibitors are now being studied to see whether they may lower breast cancer risk in postmenopausal women at high risk.
Findings from randomized controlled trials of cancer-free postmenopausal women at high risk have shown that the aromatase inhibitors exemestane and anastrozole may lower the risk of breast cancer by about half .
Unlike tamoxifen and raloxifene, exemestane and anastrozole do not appear to increase the risk of blood clots [157,280]. However, exemestane, anastrozole and other aromatase inhibitors can cause menopausal symptoms, a loss of bone density and other side effects (learn more) [281-284].
The American Society for Clinical Oncology (ASCO) and the National Comprehensive Cancer Network (NCCN) now list exemestane and anastrozole as risk-lowering drug options for postmenopausal women at higher risk of breast cancer. However, these drugs do not yet have FDA-approval for use in the risk reduction setting. These drugs are only FDA-approved for use in breast cancer treatment.
Learn about aromatase inhibitors (including exemestane and anastrozole) and breast cancer treatment.
Learn about the side effects of aromatase inhibitors.
The aromatase inhibitor drug letrozole is also being studied to see whether it may lower risk in postmenopausal women at high risk of breast cancer.
Learn about aromatase inhibitors and breast cancer treatment.
Lasofoxifene is an osteoporosis drug similar to tamoxifen and raloxifene. Early findings suggest lasofoxifene may reduce the risk of estrogen receptor-positive breast cancer in women at risk for osteoporosis [291-292]. More data are needed to confirm these findings.
If you are at higher risk of breast cancer and are considering joining a clinical trial of risk-lowering drugs, discuss the potential risks and benefits with your health care provider.
BreastCancerTrials.org in collaboration with Susan G. Komen offers a custom matching service that can help you find a clinical trial on risk reduction for healthy women and women at high risk of breast cancer.
Learn about clinical trials.
Methods to assess breast cancer risk currently under study include :
These procedures remove cells from the breast. A pathologist looks at the cells under a microscope. Abnormal (atypical) cells may be linked to an increased risk of breast cancer.
The procedures differ in how the cells are removed from the breast.
Ductal lavage uses a small tube to flush out fluid from the nipple. This fluid contains breast cells. The procedure causes some discomfort .
Ductal lavage has not yet been shown to be effective for breast cancer risk assessment . However, it is becoming more common in the U.S. and many breast centers now offer it to women at higher risk.
More research is needed to learn how to use the findings from ductal lavage.
Nipple aspiration (such as the HALO test) uses a breast pump (and sometimes massage) to remove fluid from the nipple.
Nipple aspiration is becoming more common in the U.S. and many breast centers now offer it to women at higher risk. However, more data are needed to learn how to use the findings from this test.
RPFNA uses a thin needle to remove cells from about 10 areas near the areola. This procedure is more invasive and causes more discomfort than ductal lavage, nipple aspiration or fine needle aspiration done for diagnosis. RPFNA is mostly offered in clinical studies.
At this time, findings from ductal lavage, nipple aspiration or RPFNA should not affect a woman's decision to take risk-lowering drugs (tamoxifen or raloxifene), get preventive surgery or join a risk reduction clinical trial. They should also not be used to assess risk for use in breast cancer screening recommendations. More research is needed to learn how to best use the findings from these tests.
If you are interested in one of these tests, talk to your health care provider. He/she may be able to give you a referral to a breast center with expertise in risk assessment and risk reduction.
Ductal lavage, nipple aspiration and RPFNA are under study for risk assessment. Risk assessment should not be confused with breast cancer screening (tests to find cancer early). In 2013, the U.S. Food and Drug Administration issued an alert warning people that tests such as nipple aspiration should never be used as a substitute for mammography and other breast cancer screening tools .
Facts for Life: Clinical Trials