Clinical characteristics and prognosis of elderly nasopharyngeal carcinoma patients receiving intensity-modulated radiotherapy.

PURPOSE: To evaluate the clinical characteristics and prognosis of elderly nasopharyngeal carcinoma (NPC) patients receiving intensity-modulated radiotherapy (IMRT). METHODS: From June 2008 to October 2014, 148 newly diagnosed non-metastatic elderly NPC patients (aged >/= 70 years) receiving IMRT were recruited. Comorbid condition was evaluated using the age-adjusted Charlson Comorbidity Index (ACCI). Kaplan-Meier method was used to estimate survival rates and the differences were compared using log-rank test. Hazard ratio (HR) and the associated 95% confidence interval (CI) were calculated using Cox proportional hazard model by means of multivariate analysis. RESULTS: The median follow-up time was 66.35 months. Estimated OS rate at 5 years for the entire group was 61.8% (95% confidence interval [CI] 0.542-0.703). The 5-year OS rate of RT alone group was 58.4% (95% [CI] 0.490-0.696) compared with 65.2% (95% [CI] 0.534-0.796) in CRT group (p = 0.45). In patients receiving IMRT only, ACCI score equal to 3 was correlated with superior 5-year OS rate in comparison with higher ACCI score 62.1% (95% [CI] 0.510-0.766) to 48.5% (95% [CI] 0.341-0.689), respectively; p = 0.024). A 5-year OS rate of 63.1% (95% [CI] 0.537-0.741) was observed in patients younger than 75 years old compared with 57.5% (95% [CI] 0.457-0.723) in patients older (p = 0.026). Patients with early-stage disease (I-II) showed better prognosis than patients with advanced-stage (III-IV) disease (5-year OS, 72.3-55.4%, respectively; p = 0.0073). The Cox proportional hazards model suggested that age independently predicted poorer OS (HR, 1.07; 95%CI 1.00-1.15, p = 0.04). CONCLUSION: The survival outcome of patients aged >/= 70 years receiving IMRT only was similar to chemoradiotherapy with significantly less acute toxicities. Among the population, age is significantly prognostic for survival outcomes.