Postoperative Radiation Therapy in Oral Cavity Verrucous Carcinoma

Objectives/Hypothesis We investigate the clinicopathologic and treatment factors associated with the use of postoperative radiation therapy (PORT) and its effect on overall survival (OS) for patients with oral cavity verrucous carcinoma (VC). Study Design Retrospective cohort study. Methods A retrospective cohort study of the National Cancer Database (NCDB) from 2006 to 2015 was performed. Multivariable logistic regression was used to identify independent predictive factors associated with the use of PORT. Cox Regression survival and propensity score analyses were used to evaluate the effect of PORT on mortality. Results A total of 356 adult patients with primary oral cavity VC who underwent definitive surgical resection were identified. A total of 10.7% of patients underwent definitive surgical resection followed by PORT. Variables associated with PORT included distance to the hospital per 10 miles (adjusted odds ratio [aOR], 0.81 [95% confidence interval (CI), 0.70-0.95]) and stage III-IV disease (aOR, 12.13 and 23.92, respectively). Multivariable Cox regression survival analysis indicated no evidence of survival benefit in patients undergoing PORT compared to surgery alone (adjusted hazard ratio 1.50 [0.74-3.05], P = .23). Propensity score analysis also showed no OS benefit with the use of PORT (P = .41). Conclusions Variables associated with the use of PORT on multivariable analysis included closer distance to hospital and stage III-IV disease. No clear survival benefit with PORT was identified on either multivariable survival analysis or propensity score analysis. These results suggest that surgery alone with negative margins may be the optimal treatment for patients with oral cavity VC. Level of Evidence 4 Laryngoscope, 2022