Ten-year survival outcomes for patients with nasopharyngeal carcinoma receiving intensity-modulated radiotherapy: An analysis of 614 patients from a single center

Objectives: Intensity-modulated radiotherapy (IMRT) has been applied in nasopharyngeal carcinoma (NPC) for nearly twenty years, while little is known about the ten-year survival outcomes. This study aimed at evaluating the 10-year survival outcomes for patients with NPC receiving IMRT. Materials and methods: Data on 614 patients with newly diagnosed, non-disseminated NPC treated by IMRT between 2004 and 2008 were retrospectively reviewed. Survival outcomes stratified by tumor stage were compared. Results: The median follow-up duration was 112.7 months (range, 7.6-156.8 months) for the entire cohort. The 10-year local relapse-free survival rates for T1, T2 and T3 were 94.2%, 92.5% and 91.4% (P > 0.05), respectively, and significantly higher than that of T4 disease (79.3%, P < 0.05 for all rates). As N category increased from N0 to N3, the 10-year distant metastasis-free survival rates significantly decreased accordingly (P < 0.01 for all rates). Furthermore, the 10-year overall survival rates were 100%, 87.1%, 75.5% and 55.6% for stage I, II, III and IV, respectively (P < 0.05 except stage I and II). Multivariate analysis established tumor stage and age as independent prognostic factors. Late toxicities were assessable for 495 (80.6%) patients and most were Grade I/II damages. Xerostomia (387 of 489, 79.1%) and hearing impairment (212 of 495, 42.8%) remained the most troublesome. Conclusion: IMRT could achieve satisfactory survival outcomes for NPC patients with acceptable late toxicities. However, distant control still remains poor, especially for patients with N3 disease. (C) 2017 Elsevier Ltd. All rights reserved.