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

Abstract

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 112.7months (range, 7.6-156.8months) 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.

Keywords: 10-year survival outcomes; Intensity-modulated radiotherapy; Nasopharyngeal carcinoma; Prognosis; Retrospective study.