Overall Survival After Endoscopic Surgery Versus Radiation As The Initial Treatment In Oropharyngeal Squamous Cell Carcinoma

Chemoradiation therapy (CRT) and radiation therapy (RT) offer the potential for organ preservation over surgery for patients with squamous cell carcinoma of the oropharynx (OPC). However, CRT can result in significant morbidity, which has led to increasing interest in minimally invasive endoscopic head and neck surgery (eHNS) techniques such as transoral laser microsurgery and transoral robotic surgery. While there are increasing data supporting the use of eHNS for HPV+ OPC, which has a favorable prognosis, the use of eHNS is not well described for human papillomavirus-negative (HPV-) OPC patients, who have a poorer prognosis. We used the National Cancer Data Base (NCDB) to evaluate factors associated with the use of eHNS as well as overall survival (OS) in HPV- OPC patients compared to definitive CRT/RT. This study included T1-3N0-2bM0 HPV- OPC patients diagnosed between 2010 and 2012 who received either definitive CRT/RT or eHNS as initial treatment. Binary logistic regression (LR) was performed to determine factors associated with receiving eHNS. Cox regression (CoxR), adjusted for patient and tumor factors, was used to compare OS hazard ratios (HR). Propensity score matching separated patients into cohorts with low, moderate, and high likelihood of receiving eHNS for Kaplan-Meier survival comparison. We identified 1562 HPV- OPC patients with a median age of 59 years. Initial therapy was CRT/RT (84.2%) or eHNS (15.8%). Among eHNS patients, 9.8% were cT3, 61.8% were cN0-1, 32.8% had positive margins, and 64.8% received adjuvant therapy (14.8% RT, 50.0% CRT). Among RT patients, 29.1% were cT3, 45% were cN0-1, 84.0% received concurrent chemotherapy, and 25.3% had neck dissections after RT. Factors associated with an increased likelihood of eHNS on LR were tonsillar primary, treatment at an academic center, and lower clinical stage. In CoxR, eHNS was not associated with improved OS (HR 0.631; confidence interval [CI] 0.421-1.134; P=.144). In propensity score matching, 2-year OS was improved for eHNS versus CRT/RT patients in the high likelihood cohort (94.5%; CI 91.4-97.6 vs 81.0%; CI 78.1-83.9; P=.011), but not the low likelihood cohort (80.1%; CI 71.9-88.6 vs 75.8% CI 73.0-78.6, P=.782). While HPV- OPC patients who were selected to receive eHNS in the NCDB generally had more favorable clinical tumor stage, nearly two-thirds also received adjuvant CRT/RT. While recognizing the potential influence of patient selection that is not captured by covariates available in the NCDB, we did not find a significant OS difference among patients who received initial CRT/RT or eHNS. Prospective studies are needed to clarify whether a subset of HPV- OPC patients derive benefit from eHNS and whether the quality of life is impacted in eHNS patients by the high incidence of adjuvant therapy.