Radiotherapy in Metastatic Oropharyngeal Cancer.

Abstract

The role of locoregional radiotherapy for metastatic oropharyngeal squamous cell cancer (OPSCC) is unclear. We investigated the impact of head and neck radiotherapy on survival in de novo metastatic OPSCC patients who received systemic therapy. We queried the NCDB from 2004-2015 for metastatic OPSCC patients at diagnosis with known HPV-status who received systemic therapy. The association of head and neck radiotherapy with overall survival was analyzed using the Kaplan-Meier method, Cox proportional hazards model, and propensity score-matched analysis adjusting for demographic and disease-specific prognostic factors. Of the 2,139 patients with metastatic OPSCC who presented with metastases and received systemic treatment, we identified 556 patients with known HPV-status. Among these 556 patients, 49% were HPV-positive and 56% received head and neck radiotherapy. With a median follow-up of 17.5 months (IQR 6.0-163.4 months), radiotherapy was associated with significantly improved 1-year OS (67% vs 58%, log-rank P < .001) which remained significant on MVA (HR 0.78 95% CI 0.62-0.97 P = .029). In HPV-status subgroup analysis, a survival benefit was identified in HPV-positive patients (1-year OS 77% vs 67%, log-rank P < .001) but not in HPV-negative patients. Results were consistent on a propensity score-matched analysis of 212 HPV-positive matched patients (HR 0.66, 95% CI 0.49-0.83, P < .001). The survival of metastatic OPSCC remains limited. In this large series of patients with known HPV-status, head and neck radiotherapy was associated with longer survival in those with HPV-associated disease. These data could guide management of this challenging group of patients for head and neck cancer practitioners. 3 Laryngoscope, 131:E1847-E1853, 2021.