[Effects of Dexamethasone Reduction on Chemotherapy Prophylactic Antiemetic Therapy for Gastrointestinal Cancer under Dexamethasone Supply Difficulties during COVID-19].

Due to supply difficulties and other factors associated with COVID-19, oral dexamethasone became less readily available. To address this limitation, we investigated the effect of adjusting prophylactic antiemetic therapy on the efficacy of anticancer drug treatment. This study included patients in the gastrointestinal oncology unit of our hospital who received a regimen containing moderately emetogenic risk anticancer drugs between September 2021 and August 2022. We retrospectively analyzed medical records to assess the treatment regimen, prophylactic antiemetic therapy, oral dexamethasone dose reduction, presence of emetic events during the first course, use of additional antiemetic agents for prominent nausea and vomiting, and the complete response(CR)rate. The study included 98 patients with a median age of 71 years. The overall CR rate was 95% in the standard-dose dexamethasone group and 92.3% in the dexamethasone-reduced group(p=0.68). The CR rates for oxaliplatin- and irinotecan-based regimens were 92.9% and 100% in the dexamethasone-reduced group and 91.5% and 94.7% in the standard-dose dexamethasone group. In this study, the CR rates were not significantly different between the dexamethasone reduction and standard-dose groups. This may be due to the use of steroid-sparing or triple therapy by physicians, depending on the patient's risk factors. Therefore, the prophylactic antiemetic therapies for individual patients must be continued to examine.