Relationship between renal dysfunction and oral mucositis in patients undergoing concurrent chemoradiotherapy for pharyngeal cancer: A retrospective cohort study

Background/Aim: The aim of this retrospective cohort study was to investigate the association between renal dysfunction (RD) and the development of oral mucositis (OM) in patients undergoing concurrent chemoradiotherapy (CCRT) for pharyngeal cancer including radiation to the oral cavity. Patients and Methods: Of 130 patients diagnosed as having pharyngeal cancer who received CCRT at the Okayama University Hospital Head and Neck Cancer Center, 44 were finally selected. Results: During the observation period, 24 (54.5%) patients experienced severe OM (grade 3). The Cox proportional hazards regression model demonstrated that RD (hazard ratio(HR)=2.45, 95% confidence interval(CI)=1.067-6.116, p=0.035) and nasopharynx/oropharynx as center of the irradiated area (HR=2.56, 95% CI=1.072-5.604, p=0.034) were significantly associated with the incidence of severe OM (grade 3). Conclusion: In patients with pharyngeal cancer treated with CCRT including radiation to the oral cavity, RD at baseline can be a risk factor for developing severe OM.