An NCDB Analysis Investigating Outcomes in HPV Negative Oropharyngeal Carcinoma - An Attempt to Bridge the Gap Due to Lack of Accrual in RTOG 1221

Abstract

Transoral robotic surgery (TORS) represents a considerable technological advance in surgical technique in head and neck squamous cell carcinoma (HNSCC). RTOG 1221 was a proposed study of intensified local therapy for T1-2, N0-2b, HPV negative HNSCC of the oropharynx with TORS; this study closed after 15 months due to zero patient accrual1. In place of the prospective trial, the National Cancer Database (NCDB) can be utilized to follow survival outcomes in this patient population. Retrospective review was performed of the National Cancer Data Base 2004 – 2015 data for T1-2, N0-2b, oropharynx HNSCC. Patients were included for analysis if they were treated according to the regimens of RTOG1221 with TORS +/- adjuvant therapy, or chemoRT alone. Adjuvant treated must have been started within 3 months of TORS. Kaplan Meier overall survival (OS) estimates and log rank analysis was performed. A total of 1698 T1-2, N0-2b patients with HPV negative oropharyngeal HNSCC were analyzed. Median survival was not reached in either cohort. 126 patients had TORS +/- adjuvant therapy, with a median follow-up of 36.55 months (SD 17.53 months). This cohort had a 2-year survival estimate of 88.2% with standard error of 0.03. 1572 patients had chemoRT alone, with a median follow-up of 33.15 months (SD 18.33 months). This cohort had a 2-year survival estimate of 84.1% with standard error of 0.009. Log rank analysis of these groups demonstrates no statistically significant difference in OS, with a chi-square of 1.754 and a p-value of 0.185. OS outcomes of HPV negative patients treated with TORS +/- adjuvant therapy were not statistically significantly different than those treated with concurrent chemoRT alone. This NCDB data may offer insight into the role of TORS in treatment escalation for HPV negative oropharyngeal HNSCC, especially as this data matures over the next several years.