MDNews - Central New Jersey

Y ET TH E U PDATE D statement acknowledges that uptake of the drugs has been low in the intervening years, and notes that concerns about side effects may have discouraged women from trying the drugs or continuing to take them. Mark H. Ebell, MD, MS, Associate P rofessor of Epidem iolo g y at t he University of Georgia College of Public Health and a member of the USPSTF, believes that even given the value of the drugs, deciding whether to use them is a complicated calculus. "The medications used to prevent breast cancer have potential benefits and harms," Dr. Ebell says. "W hile the benefits are likely to outweigh the harms for many high-risk women, it is still a difficult decision." The Background After lung cancer, breast cancer is the leading cause of cancer deaths among women, according to the American Cancer Society. In 2014, approximately 233,000 new cases of invasive breast cancer will be diagnosed, and roughly 40,000 American women are expected to die of the disease. For women at high risk for breast cancer, chemoprevention reduces the incidence of the disease. Currently, the two most thoroughly studied and widely prescribed chemoprevention drugs are tamoxifen and raloxifene. Both are selective estrogen receptor modulators (SER Ms). SER Ms limit the effects of estrogen, a hormone that a ffects breast cancer development. Tamoxifen blocks the effects of estro- gen in tissues throughout the body, although in the uterus it performs a f unction similar to that of estrogen by promoting normal grow th of the uterine lining. Raloxifene also limits the ef fects of estrogen throughout the body; however, it does not have effects similar to those of tamoxifen in the uterus. Balancing Benefits and Harms The USPSTF based its updated rec- ommendation on a systematic review of chemoprevention drugs, including tamoxifen and raloxifene. The medi- cations were shown in randomized, placebo-controlled trials to be effective in reducing breast cancer incidence among high-risk women. Tamoxifen prevented about half of breast cancers in high-risk women, decreasing their risk of developing bre a s t c a nc er f rom 4 p erc ent t o approximately 2 percent. Raloxifene, an osteoporosis drug sold under the brand name Evista, was slightly less effective than tamoxifen in prevent- ing cancers. However, it was also less likely to produce adverse effects. For both drugs, potential side effects are quality-of-life impacting and include blood clots, cataracts, uterine cancer and menopause symptoms, such as hot f lashes and night sweats. The review's acknowledgement that concerns about side effects may inf lu- ence a woman's decision to take the drugs is something Judy Garber, MD, MPH, a medica l oncolog ist at t he Da na-Fa rber Ca ncer Institute, ha s witnessed. She considers potential side effects such as hot f lashes a significant barrier — even if they frequently do not materialize. "Many women won't have any, but they may need to try the drugs to see how they do …," Dr. Garber told The Boston Globe in 2013. She added that there is considerable public skepticism about medication safety. T h e U S P S T F r e c o m m e n d a t io n emphasizes that only a small number of women a re at increased risk for breast cancer and that only a fraction of those would benefit from prophylactic medications. The organization recom- mends against the routine prescribing of chemoprevention medications to REMOVING THE COST BARRIER IN JANUARY 2014, the U.S. Department of Health and Human Services announced that breast cancer prevention drugs must be fully covered by most health insurance companies and employer plans under the Affordable Care Act's provisions for preventive services. Women at increased risk of breast cancer may now receive chemoprevention drugs, including tamoxifen and raloxifene, without a co-pay or other out-of-pocket cost. NEW AVENUE TOWARD PREVENTION IN A STUDY recently published in The Lancet, researchers found that anastrozole, an aromatase inhibitor sold under the brand name Arimidex, prevented many breast cancers affected by estrogen (hormone receptor-positive cancer). In the study, which included 3,800 high-risk, postmenopausal women, anastrozole reduced the risk of invasive breast cancers by 53 percent — slightly better than tamoxifen and raloxifene. The researchers report that side effects were only slightly higher in the anastrozole groups than in the control group, suggesting the effects were unrelated to the treatment. THE U.S. PREVENTIVE SERVICES TASK FORCE (USPSTF) RECENTLY RENEWED ITS 2002 RECOMMENDATION THAT BREAST CANCER PREVENTION DRUGS BE OFFERED TO HIGH-RISK WOMEN WHO ARE AT LOW RISK FOR SIDE EFFECTS, AND IT ADDED GUIDANCE FOR CLINICIANS ABOUT WHEN TO CONSIDER PRESCRIBING THE DRUGS. Assessing Low Usage of Breast Cancer Prevention Drugs Fear Factor: reduce breast cancer risk in women who are not at high risk for the disease. In updating its recommendation, the task force added that clinicians should "engage in shared, informed decision making with women who are at increased risk for breast cancer about medications to reduce their risk. For women who are at increased risk for breast cancer and at low risk for adverse medication effects, clinicians should offer to prescribe risk-reducing medica- tions, such as tamoxifen or raloxifene." Mea nwhile, Dr. Ebell notes, t he is s ues t h at m ay d iscou ra ge some women f rom t a k ing brea st ca ncer prevention drugs highlight the need for further study and new approaches. "We need both better tools to help women a nd t heir physicia ns ma ke these challenging decisions and more research to develop drugs that prevent breast cancer but have fewer adverse effects," he says. ■ By Jonelle Todd CORE CORE SPECIAL CLINICAL SECTION: WOMEN'S HEALTH 1 2 | Central New Jersey MD NEWS ■ M D N E W S . CO M

• Cover