Concurrent chemoradiotherapy versus radiotherapy alone in older patients with stage II nasopharyngeal carcinoma after intensity-modulated radiotherapy: A propensity score-matched cohort study

Abstract

Background and purpose: Whether concurrent chemoradiotherapy (CCRT) benefits the older (age ≥ 60 years) patients with stage II nasopharyngeal carcinoma (NPC) has not been determined. This study aimed to compare the outcomes and toxicities of CCRT with Intensity-Modulated Radiotherapy (IMRT) alone in older patients with stage II NPC.

Materials and methods: Between January 2010 and December 2017, 220 older (age ≥ 60 years) patients with stage II NPC were analyzed. A pair of 53 patients were matched between the CCRT group and RT group by using propensity score matching (PSM) in terms of age, sex, pathological type, T and N stage, ACE-27 scores, CRP, LDH and Hb. Cancer-specific survival (CSS), progression-free survival (PFS), locoregional relapse-free survival (LRRFS) and distant metastasis-free survival (DMFS) were analysed by the Kaplan-Meier method and log-rank test. Multivariate analysis was performed to assess the prognostic risk factors by using a Cox's proportional hazards regression model. Treatment toxicities were clarified and compared between the two groups by using the χ² test.

Results: The median follow-up time of the whole cohort was 82.0 months (range, 11-151 months). PSM analysis indicated that compared with the RT group, significantly higher 5-year CSS (98.1 % vs. 83.0 %, P = 0.02), PFS (98.1 % vs. 79.2 %, P = 0.01) and DMFS (100.0 % vs. 92.4 %, P = 0.04) were observed in the CCRT group. Multivariate analysis showed that CCRT was an independent prognostic factor predicting CSS (HR, 0.34; 95 % CI, 0.15-0.79; P = 0.01), PFS (HR, 0.48; 95 % CI, 0.25-0.93; P = 0.03), and LRRFS (HR, 0.36; 95 % CI, 0.14-0.90; P = 0.03), and a higher ACE-27 score predicted a worse CSS. Patients in the CCRT group experienced higher frequencies of the acute toxicities than patients in the RT group. Late complications were comparable between the two groups.

Conclusion: CCRT significantly improved the survival benefits for the older patients with stage II NPC compared with IMRT alone without adding late complications, whereas increased some of the treatment-associated acute toxicities.

Keywords: Chemotherapy; Intensity-modulated radiotherapy; Nasopharyngeal carcinoma; Older; Prognosis; Radiotherapy.