LAUSR

Overuse of low-value oncology services has received increasing attention recently.1 National campaigns, such as “Choosing Wisely,” have prompted medical specialty societies to identify areas for reducing use of low-value services. The use of antiemetic drugs to prevent chemotherapy-induced nausea and vomiting (CINV) exemplifies an area with high potential for overuse and was targeted in the 2013 set of Choosing Wisely recommendations put forth by the American Society of Clinical Oncology (ASCO).2 Specifically, oncologists were cautioned not to use potent antiemetics (ie, neurokinin-1 receptor antagonists), which are intended for use among patients taking chemotherapy with a high risk of CINV, for patients initiating chemotherapy with a low or moderate risk of CINV.2 The past 2 decades have seen substantial advances in the development of antiemetic drugs. Namely, serotonin receptor antagonists and neurokinin-1 receptor antagonists have widened tolerability of potentially beneficial chemotherapy regimens with a moderate to high emetogenic risk. However, these advances have come at a price. In addition to their substantial cost to patients and the health care system, when used unnecessarily (ie, with minimalto low-risk chemotherapy), potent antiemetic agents may expose patients to excess toxic effects.3 For several years, oncology professional organizations, including ASCO, have produced and endorsed clinical practice guidelines specifying appropriate use of antiemetics.4 However, adherence to the guidelines has been suboptimal.5 Although overuse of antiemetics among patients taking chemotherapy drugs with lower risk of CINV is concerning because of the potential for excess cost and toxic effects, underuse can affect patients’ quality of life6 and their adherence to prescribed chemotherapy regimens.7 Even so, underuse of antiemetics is well documented among patients taking chemotherapy drugs with a higher risk of CINV. For example, in a study of Texas Medicare beneficiaries with lung cancer initiating platinum-based chemotherapy regimens between 2001 and 2007, only 10% of patients received neurokinin-1 receptor antagonists after their inclusion in guidelines in 2006.8 Rates of use of long-recommended serotonin receptor antagonists and corticosteroids were also low, at approximately 80% and 65%, respectively. In addition, an analysis of women with early-stage breast cancer beginning adjuvant chemotherapy containing an anthracycline and cyclophosphamide between 2006 and 2012 revealed that only 40% of women received a neurokinin-1 receptor antagonist in accordance with guideline recommendations.9 In this issue of JAMA Oncology, Encinosa and Davidoff10 present valuable data about the potential overuse of antiemetics to prevent CINV. In their large observational, claimsbased study of privately insured patients with cancer initiating chemotherapy between 2008 and 2015, the authors examined overuse of antiemetics relative to recent guidelines, as well as associated expenditures. In particular, they were interested to learn whether overuse of antiemetics declined with the release of the 2013 ASCO Choosing Wisely recommendation.2 The authors observed substantial overuse of antiemetics in the period before the Choosing Wisely recommendation, including overuse among patients beginning a chemotherapy regimen with a minimal emetogenic risk, where no prophylaxis is recommended.10 Specifically, in the minimaland low-risk settings, 15% and 20% of patients received stronger antiemetic therapy than recommended. Among patients beginning moderateor high-risk chemotherapy regimens, who were represented as a single group in this study, 32% appeared to preemptively fill prescriptions for drugs typically reserved for breakthrough symptoms several days after chemotherapy. The largest difference in spending between a guideline-consistent antiemetic regimen and an antiemetic regimen with overuse was observed for the intravenous chemotherapeutic agents at low risk of CINV: $452 or 587%. The study by Encinosa and Davidoff10 suggests that the Choosing Wisely recommendation had a limited effect on overuse of antiemetics to prevent CINV. In the 6 months following the release of the Choosing Wisely recommendation, overuse of antiemetics declined for all intravenous chemotherapy, but not for orally administered chemotherapy. The decline was short-lived, however. Following this initial 6-month period, overuse increased again in all chemotherapy groups except for the group receiving low-risk intravenous chemotherapy. Given the existence of clear guidelines concerning antiemetic use for CINV prophylaxis, why is inappropriate use persistent? As suggested by Encinosa and Davidoff,10 insurer practices may play a role. Currently, Medicare covers the 3-drug oral regimen of a neurokinin-1 receptor antagonist, serotonin receptor antagonist, and a corticosteroid not only for highly emetogenic chemotherapy regimens, for which guidelines suggest all 3 drugs are necessary to achieve sufficient CINV prophylaxis, but also for moderately emetogenic chemotherapy regimens.11 Not only do guidelines not recommend the addition of a neurokinin-1 receptor antagonist for patients beginning moderately emetogenic chemotherapy, the 2013 ASCO Related article Opinion