Factors associated with severe oral mucositis and candidiasis in patients undergoing radiotherapy for oral and oropharyngeal carcinomas: a retrospective multicenter study of 326 patients

Purpose The present retrospective multicenter study intended to investigate the factors associated with severe oral mucositis and candidiasis in patients undergoing radiotherapy for oral and oropharyngeal carcinomas. Methods A total of 326 patients who underwent radiotherapy for oral and oropharyngeal cancers were enrolled in the study. The patients’ age, sex, body mass index, primary site, diabetes, serum albumin, creatinine, hemoglobin, leukocyte and lymphocyte, concurrent cisplatin or cetuximab, method of radiation, total radiation dose, feeding route, use of spacers, pilocarpine hydrochloride, and corticosteroid ointment were examined, and the associations of each variable with oral mucositis and candidiasis were analyzed by multivariate Cox regression analysis. Results Grade 3 oral mucositis occurred in 136 (41.7%) patients. Male sex, oropharyngeal cancer, low hemoglobin levels, low leukocytes or lymphocytes, concurrent cisplatin or cetuximab, and oral feeding were found to be significantly associated with a higher incidence of severe oral mucositis. Oral candidiasis occurred in 101 (31.0%) patients. Oropharyngeal cancer, low leukocyte count, and oral mucositis of grade 2 or higher were found to be significantly associated with a higher incidence of oral candidiasis. The use of a topical steroid ointment was not found to be a risk factor for oral candidiasis. Conclusions The present retrospective study demonstrated that certain factors may predispose patients with oral and oropharyngeal cancers receiving radiotherapy to develop severe oral mucositis and oral candidiasis. A preventive strategy for severe oral mucositis needs to be established in the future for high-risk cases.