Pretreatment serum vitamin level predicts severity of radiation‐induced oral mucositis in patients with nasopharyngeal carcinoma.

Background: Radiation‐induced mucositis (RIOM) is a common radiotherapy toxicity. We aimed to evaluate the relationship of serum vitamin status with RIOM among nasopharyngeal carcinoma (NPC) patients who underwent radiotherapy. Methods: NPC patients who underwent concurrent chemoradiotherapy with available pretreatment serum vitamin values were included. Serum vitamin levels and clinical characteristics were collected. Logistic regression analysis and receiver operating characteristic curves were conducted to explore the potential risk factors and corresponding cut‐off values for severe RIOM. Results: Two hundred and forty NPC patients were enrolled. Multivariate regression analysis showed that mean oral cavity radiation dose (OR = 2.042; 95% CI = 1.585‐2.630; P <.001), weekly concurrent chemotherapy (OR = 3.898; 95% CI = 1.085‐14.004; P =.037), lower serum level of vitamin B2 (OR = 0.951; 95% CI = 0.924‐0.978; P <.001), and vitamin C (OR = 0.455; 95% CI = 0.346‐0.598; P <.001) were independent risk factors for developing severe RIOM. Conclusions: The findings of this study revealed that serum vitamin status could predict the severity of RIOM, providing a theoretical basis for the prevention and treatment of RIOM. [ABSTRACT FROM AUTHOR]