Correlation of planned dose to area postrema and dorsal vagal complex with clinical symptoms of nausea and vomiting in oropharyngeal cancer (OPC) patients treated with radiation alone using IMRT

摘要

Objective This study aimed to correlate planned dose to the nausea center (NC)-area postrema (AP) and dorsal vagal complex (DVC)-with nausea and vomiting symptoms in oropharyngeal cancer (OPC) patients treated with intensity-modulated radiation therapy (IMRT) without chemotherapy. We also investigated whether it was possible to reduce doses to the NC without significant degradation of the clinically accepted treatment plan.Methods From November 2004 to April 2009, 37 OPC patients were treated with definitive or adjuvant IMRT without chemotherapy. Of these, only 23 patients had restorable plans and were included in this analysis. We contoured theNC with the assistance of an expert, board-certified neuro-radiologist. We searched for correlation between the delivered dose to the NC and patient-reported nausea and vomiting during IMRT. We used one-paired two-sample t test assuming equal variances to compare differences in dose to NC between symptomatic and asymptomatic patients. We then replanned each case to determine if reduced dose to the NC could be achieved without compromising coverage to target volumes, increasing unwarranted hotspots, or increasing dose to surrounding critical normal tissues.