Objective The goal of this study is to determine the effect of primary surgery vs radiotherapy (RT) on overall survival (OS) in patients with early stage oral cavity squamous cell carcinoma (OCSCC). In addition, this study attempts to identify factors associated with receiving primary RT. Study Design Retrospective cohort study. Setting National Cancer Database (NCDB, 2004-2013). Subjects and Methods Reviewing the NCDB from 2004 to 2013, patients with early stage I to II OCSCC were identified. Kaplan-Meier estimates of survival, Cox regression analysis, and propensity score matching were used to examine differences in OS between primary surgery and primary RT. Multivariable logistic regression analysis was performed to identify factors associated with primary RT. Results Of the 20,779 patients included in the study, 95.4% (19,823 patients) underwent primary surgery and 4.6% (956 patients) underwent primary RT. After adjusting for covariates, primary RT was associated with an increased risk of mortality (adjusted hazard ratio [aHR], 1.97; 99% confidence interval [CI], 1.74-2.22). On multivariable analysis, factors associated with primary RT included age ≥70 years, black race, Medicaid or Medicare insurance, no insurance, oral cavity subsite other than tongue, clinical stage II disease, low-volume treatment facilities, and earlier treatment year. Conclusion Primary RT for early stage OCSCC is associated with increased mortality. Approximately 5% of patients receive primary RT; however, this percentage is decreasing. Patients at highest risk for receiving primary RT include those who are elderly, black, with public insurance, and treated at low-volume facilities.
Keywords: NCCN guidelines; National Cancer Database; oral cavity cancer; overall survival; radiotherapy; squamous cell carcinoma; surgery.