Effect Of Dose-volume On Radiation-induced Nasopharyngeal Ulcer In Patients With Primary Nasopharyngeal Carcinoma Treated With Intensity-modulated Radiation Therapy

This retrospective study was designed to analyze the correlation between dose-volume and radiation-induced nasopharyngeal ulcer(RINU)in patients with primary nasopharyngeal carcinoma(NPC)treated with intensity-modulated radiation therapy(IMRT).Clinical data were collected for 599 patients with newly diagnosed NPCwho had completed IMRT.The relationship between RINU and IMRT dose-volume were statistically analyzed with receiver operating characteristics curves(ROC)and the Chi-square test.Nutritional status during and after treatment was compared between patients with vs.without RINU.The entire cohort was randomly divided into 2 subgroups.An ROC curve was generated to identify a rational cut-off point for tumor volume(ratio)after exposure to 7400 c Gy in the first subgroup(299 patients).After obtaining a threshold for tumor volume(ratio),the remaining patients(n = 300)were divided into two groups in order to compare the incidence of RINU.The results obtained showed that dose-volume had no effect on the incidence of RINU(p > 0.05).Nutrition-related parameters differed significantly between patients with vs.without RINU(p < 0.05).The results obtained show that the incidence of RINU is not related to IMRT dose-volume in the treatment of primary NPC.The incidence of RINU was found to be related to nutritional status during and after radiation therapy.