Predictors of survival in patients undergoing oropharyngeal surgery for cancer recurrence after radiation therapy.

PURPOSE: The incidence of oropharyngeal squamous cell carcinoma continues to rise with the majority of patients receiving definitive or adjunctive radiation. For patients with locoregional recurrence after radiation, optimal treatment involves salvage surgery. The aim of this study is to identify factors that predict survival to ultimately improve patient selection for salvage surgery. METHODS: Retrospective cohort study at an NCI-designated cancer center. We analyzed patients with a history of head and neck radiation who presented with persistent/recurrent or second primary disease requiring salvage oropharyngeal resection from 1998-2017 (n = 120). Patients were stratified into three classes based on time to recurrence and presence of laryngopharyngeal dysfunction. Primary outcomes were 5-year overall survival (OS) and disease specific survival (DSS). RESULTS: Median OS was 27 months (median follow-up 20 months). Five-year OS was 47% for class I (recurrence > 2 years), 26% for class II (recurrence </= 2 years), and 0% for class III (recurrence </= 2 years and laryngopharyngeal dysfunction), (p < 0.0001). Five-year DSS showed significant differences between classes (p < 0.0001). On multivariate analysis, class remained predictive of OS (p = 0.04- < 0.001) and DSS (p = 0.04-0.001). Adjuvant radiation after salvage surgery with negative margins showed superior OS (71% vs. 28%, p = 0.01) and DSS (83% vs 37%, p = 0.02) compared to surgery alone and was a significant predictor of improved survival on multivariate analysis (HR 0.1, p = 0.04). CONCLUSION: This study identified a subset of patients with oropharyngeal cancer recurrence within two years of initial treatment and with laryngopharyngeal dysfunction who have poor outcomes for salvage surgery.