Abstract
BACKGROUND: Radiotherapy (RT) combined with chemotherapy is the standard treatment for T1-2N1M0 nasopharyngeal carcinoma (NPC) based on conventional radiotherapy. However, intensity-modulated radiotherapy (IMRT) has narrowed the treatment gap between RT and chemoradiotherapy. Thus, this retrospective study aimed to compare the efficacy of RT and chemoradiotherapy (RT-chemo) in treating T1-2N1M0 NPC in the IMRT era. MATERIALS AND METHODS: From January 2008 to December 2016, 343 consecutive patients with T1-2N1M0 NPC in two cancer centers were included. All patients received RT or RT-chemo, chemotherapy including induction chemotherapy (IC) + concurrent chemoradiotherapy (CCRT), CCRT, or CCRT + adjuvant chemotherapy (AC). The number of patients who received RT, CCRT, IC + CCRT, and CCRT + AC was 114, 101, 89, and 39. The survival rates were analyzed using the Kaplan-Meier method and compared using the log-rank test. Multivariable analysis was performed to identify valuable prognostic factors. RESULTS: The median follow-up time for survivors was 93 (range: 55-144) months. The 5-year overall survival (OS), progression-free survival (PFS), locoregional failure-free survival (LRFFS), and distant metastasis-free survival (DMFS) for the RT-chemo and RT groups were 93.7%, 88.5%, 93.8%, 93.8% and 93.0%, 87.7%, 91.9%, 91.2%, respectively (P>0.05 for all outcomes). No significant survival differences were found between the two groups. The T1N1M0 or T2N1M0 subgroup analysis showed that treatment outcomes had no significant differences between the RT and RT-chemo groups. After adjusting for various factors, treatment mode was not identified as an independent prognostic factor for all survival rates. CONCLUSIONS: In this study, outcomes of T1-2N1M0 NPC patients treated by IMRT alone were comparable to chemoradiotherapy, supporting the omission or postponement of chemotherapy.