Intensity-modulated radiotherapy alone compared with intensity-modulated radiotherapy plus concurrent chemotherapy in intermediate-risk nasopharyngeal carcinoma : A prospective multicenter phase II trial.

Background: This study aimed to investigate the clinical benefit of adding concurrent chemotherapy to intensity-modulated radiotherapy (IMRT) for nasopharyngeal carcinoma (NPC) patients with an intermediate risk (stage II and T3N0M0).

Methods: A multicenter phase II randomized trial was conducted in intermediate-risk NPC patients. Enrolled patients were previously untreated and aged ranged from 18 to 70 years without severe coexisting diseases. Patients were randomly assigned to receive IMRT alone or IMRT+concurrent chemotherapy (CC; three cycles of 80 mg/m cisplatin every 3 weeks). Primary endpoint was defined as 3‑year progression-free survival (PFS). The secondary endpoints were distant metastasis-free survival (DMFS), locoregional relapse-free survival (LRRFS), overall survival (OS), and treatment-associated toxicity. We registered this study with Chinese Clinical Trial Registry (CliCTR1800017132; registered July 13, 2018, study start July 13, 2018).

Results: From November 2015 to July 2019, 42 patients with stage II and T3N0M0 NPC were enrolled; 20 patients received IMRT alone while 22 patients received IMRT+CC. After a median of 58 months of follow-up, we estimated the 3‑year PFS rates as 90% (IMRT group) and 86.4% (IMRT+CC group; hazard ratio 1.387, 95% confidence interval 0.240-8.014; P = 0.719). The 3‑year PFS, OS, and cumulative DMFS and LRRFS showed no significant differences between the two groups (P > 0.05). However, the IMRT group displayed a lower incidence of nausea/vomiting, leucopenia, and dry mouth than the IMRT+CC group.

Conclusion: Adding CC to IMRT provided no survival benefit but increased treatment-associated toxicities in patients with intermediate-risk NPC.