Improvement of adherence to guidelines for antiemetic medication enhances emetic control in patients with colorectal cancer receiving chemotherapy of moderate emetic risk.

Prevention of chemotherapy-induced nausea and vomiting (CINV) according to the clinical practice guidelines is particularly important. In the present study, we investigated the adherence to the guidelines for antiemetic medication and the control of CINV in 61 patients with colorectal cancer receiving the first course of chemotherapy of moderate emetic risk at our outpatient cancer chemotherapy clinic. Furthermore, we carried out intervention to improve evidence-based antiemetic medication in another 64 patients. The rate of adherence to the antiemetic guidelines was only 6.6%; non-adherence was due mostly to the lack of dexamethasone treatment on days 2 and 3. In the interventional group, antiemetic medication adherence was markedly enhanced to 89%, which led to a significant enhancement of complete protection from nausea and vomiting during-delayed period (days 2-5 after chemotherapy) from 54% to 74% (p<0.05), although the daily dose of dexamethasone was 4 mg, lower than that recommended by the guidelines (8 mg). Finally, we evaluated the effect of dexamethasone at a daily dose of 4 mg, since little is known about the efficacy of such dose. Dexamethasone at this dose was found to be effective at elevating the rate of complete protection from nausea and vomiting during-delayed period (increase of 20%, p<0.05). These findings suggest that medication intervention to reduce the gap between guidelines and clinical practice improves the emetic control in patients with colorectal cancer receiving moderately-emetic chemotherapy.