Endoscopic surgery compared with intensity-modulated radiotherapy in resectable locally recurrent nasopharyngeal carcinoma: a multicentre, open-label, randomised, controlled, phase 3 trial

Background The role of surgery compared with reirradiation in the primary treatment of patients with resectable, locally recurrent nasopharyngeal carcinoma (NPC) who have previously received radiotherapy is a matter of debate. In this trial, we compared the efficacy and safety outcomes of salvage endoscopic surgery versus intensity-modulated radiotherapy (IMRT) in patients with resectable locally recurrent NPC. Methods This multicentre, open-label, randomised, controlled, phase 3 trial was done in three hospitals in southern China. We included patients aged 18-70 years with a Karnofsky Performance Status score of at least 70 who were histopathologically diagnosed with undifferentiated or differentiated, non-keratinising, locally recurrent NPC with tumours confined to the nasopharyngeal cavity, the post-naris or nasal septum, the superficial parapharyngeal space, or the base wall of the sphenoid sinus. Eligible patients were randomly assigned (1:1) to receive either endoscopic nasopharyngectomy (ENPG group) or IMRT (IMRT group). Randomisation was done manually using a computer-generated random number code and patients were stratified by treatment centre. Treatment group assignment was not masked. The primary endpoint was overall survival, compared between the groups at 3 years. Efficacy analyses were done by intention to treat. Safety analysis was done in patients who received treatment according to the treatment they actually received. This trial was prospectively registered at the Chinese Clinical Trial Registry, ChiCTRTRC-11001573, and is currently in follow-up. Findings Between Sept 30, 2011, and Jan 16, 2017, 200 eligible patients were randomly assigned to receive either ENPG (n=100) or IMRT (n=100). At a median follow-up of 56.0 months (IQR 42.0-69.0), 74 patients had died (29 [29%] of 100 patients in the ENPG group and 45 [45%] of 100 patients in the IMRT group). The 3-year overall survival was 85.8% (95% CI 78.9-92.7) in the ENPG group and 68.0% (58.6-77.4) in the IMRT group (hazard ratio 0.47, 95% CI 0.29-0.76; p=0.0015). The most common grade 3 or worse radiation-related late adverse event was pharyngeal mucositis (in five [5%] of 99 patients who underwent ENPG and 26 [26%] of 101 patients who underwent IMRT). Five [5%] of the 99 patients who underwent ENPG and 20 [20%] of the 101 patients who underwent IMRT died due to late toxic effects specific to radiotherapy; attribution to previous radiotherapy or trial radiotherapy is unclear due to the long-term nature of radiation-related toxicity. Interpretation Endoscopic surgery significantly improved overall survival compared with IMRT in patients with resectable locally recurrent NPC. These results suggest that ENPG could be considered as the standard treatment option for this patient population, although long-term follow-up is needed to further determine the efficacy and toxicity of this strategy. (C) 2021 Elsevier Ltd. All rights reserved.