Impact of Radiotherapy Combined With Chemotherapy on Long-Term Outcomes of Patients With Recurrent Nasopharyngeal Carcinoma

Background: It remains controversial whether the application of chemotherapy has an impact on recurrent nasopharyngeal carcinoma (rNPC) patients with salvage radiotherapy. Here, we aimed to evaluate treatment outcomes of rNPC patients and derive a prognostic model to assess the benefit of chemotherapy in patients with re-radiotherapy. Methods: This study was conducted as a retrospective study. In total, 340 rNPC patients treated with salvage intensity-modulated radiotherapy (IMRT) or radiochemotherapy (RCT) from October 2006 to September 2019 were included in this study. Overall survival (OS) was the primary outcome. Kaplan-Meier method was employed to detect the prognostic difference with Log-rank tests. The Cox regression analysis was performed to explore the potential prognostic factors while the multivariate Cox analysis was used to identify candidate variables for the prognostic model of OS. Results: The 5-year actuarial rates of OS, progression-free survival, loco-regional progression-free survival, and distant metastases-free survival did not show significant difference between the IMRT and RCT groups (P > .05). Age at recurrence and rT category were found to be the independent prognostic factors for OS. We found that rNPC patients suffered poor OS in the high-risk group (patients with higher age at recurrence and advanced rT category) (high-risk vs low-risk, HR = 1.87, 95% CI: 1.36-2.57, P < .001). Salvage RT alone may be superior to RCT for patients in the low-risk group (RCT group vs RT group, HR = 1.89, 95% CI: 1.11-3.20, P = .038). Conclusion: Salvage RT combined with chemotherapy cannot improve survival outcomes for rNPC. More novel clinical trials should be explored to develop individualized strategies to improve survival and minimize toxicities.