Management of radiation-induced nausea and vomiting with palonosetron in patients with pre-existing emesis: a pilot study

BACKGROUND: Approved almost 15 years ago for use in the chemotherapy setting, palonosetron, a 2nd generation 5-hydroxtryptamine 3 receptor antagonist (5-HT3 RA), has demonstrated efficacy in preventing chemotherapy-induced nausea and vomiting. However, its utility in the prophylaxis and treatment of radiation-induced nausea and vomiting (RINV) has yet to be evaluated. In this pilot study, we investigated the rates of control in RINV in patients with pre-existing emesis. METHODS: Patients with pre-existing emesis undergoing palliative radiotherapy to sites with emetic risk were prescribed palonosetron 0.5 mg before the start of radiation treatment, and every other day until completion of treatment. Patients were followed up in acute (day 1 of treatment to day 1 after treatment) and delayed phases (days 2-10 after treatment). Prophylaxis and rescue (PR) was defined as a decrease in anti-emetic use, or episodes of nausea and/or vomiting from baseline. Complete prophylaxis (CP) was defined as no increase in anti-emetic use, or episodes of nausea and/or vomiting. Secondary endpoints included control of nausea and quality of life (QOL), as assessed with the Functional Living Index-Emesis and the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 15 Palliative. RESULTS: Fourteen patients were enrolled. Rates of control were higher in the acute phase (n=14) for nausea (PR =42.9%, CP =42.9%) and vomiting (PR =21.4%, CP =71.4%) compared to the delayed phase (n=13) for nausea (PR =42.9%, CP =7.7%) and vomiting (PR =15.4%, CP =53.8%). CONCLUSIONS: Palonosetron appears to be safe and patients with pre-existing emesis receiving palliative radiotherapy. More studies are needed to investigate its efficacy in this patient population.