Long-term efficacy of intensity-modulated radiotherapy with or without chemotherapy in treatment of nasopharyngeal carcinoma and its influencing factors: an analysis of 454 patients

Abstract

Objective To analyze the long-term efficacy of intensity-modulated radiotherapy (IMRT) with or without chemotherapy in treatment of 454 patients with nasopharyngeal carcinoma (NPC) and its influencing factors. Methods A retrospective analysis was performed on the clinical data of 454 patients with non-metastatic NPC who received IMRT with or without chemotherapy in our center from 2007 to 2012. Prescribed doses of 69.96-73.92 Gy in 33 fractions, 69.96 Gy in 33 fractions, 60.06 Gy in 33 fractions, and 50.96 Gy in 28 fractions were applied to nasopharyngeal gross tumor volume, cervical metastatic lymph nodes, high-risk drainage area, and low-risk drainage area, respectively. In all patients, 438 received induction chemotherapy, 420 concurrent chemotherapy, and 216 adjuvant chemotherapy, most of which were based on cisplatin and taxol. The Kaplan-Meier method was used for calculating survival rates and the log-rank test was used for survival difference analysis and univariate prognostic analysis. The Cox model was used for the multivariate prognostic analysis. Results The 3-year sample size was 210. The 3-year overall survival (OS), local recurrence-free survival, nodal relapse-free survival, progression-free survival, and distant metastasis-free survival (DMFS) rates were 88.1%, 91.0%, 90.7%, 80.5%, and 85.1%, respectively. Age, T stage, and N stage were influencing factors for the OS rate (P=0.011; P=0.005; P=0.033); T stage and N stage were influencing factors for the disease progression-free survival (P=0.017; P=0.005) and DMFS (P=0.012; P=0.019). The grade ≥3 acute and late adverse reactions included hematological toxicity, oral mucositis, xerostomia, dysphagia, and brain injury. Conclusions IMRT promotes the long-term survival rates in patients with NPC. The distant metastasis is the major reason for treatment failure. The adverse reactions induced by IMRT combined with chemotherapy are tolerable. Key words: Nasopharyngeal neoplasms/radiotherapy; Radiotherapy, intensity-modulated; Prognosis