Impact of dose volume parameters and clinical factors on acute radiation oral mucositis for locally advanced nasopharyngeal carcinoma patients treated with concurrent intensity-modulated radiation therapy and chemoradiotherapy.

PURPOSE: To prospectively identify the predictive value of different dosimetric parameters and also assess the predictors of acute radiation oral mucositis (ROM). METHODS: In accordance with the RTOG scoring criteria, ninety-two patients with locally advanced nasopharyngeal carcinoma (NPC) treated with concurrent chemoradiotherapy were evaluated for acute ROM which was defined as severe when the score >/=3. Patients' medical records and dosimetric data exported from IMRT plan enable the authors to perform a statistical analysis for the parameters as potential predictors of severe ROM. RESULTS: Body weight loss and V30Gy (p=0.017 and 0.003, respectively) are related factors to severe ROM. As the receiver operating characteristics (ROC) curve shows, the threshold value of V30 for severe ROM was 73.155% (sensitivity, 0.842; specificity, 0.671), and the area under V30Gy curves was 0.753 (p=0.001). CONCLUSION: New parameters were found as predictors of severe ROM using dosimetric analysis.