UCLA

BACKGROUND: Survival outcomes for adjuvant chemoradiotherapy (aCRT) and adjuvant radiotherapy (aRT) were compared in patients with oropharyngeal squamous cell carcinoma (OPSCC) with intermediate-risk features. METHODS: We identified 2164 patients with OPSCC in the National Cancer Database without positive margins or extracapsular extension and with at least one intermediate-risk feature: pT3-T4 disease, ≥two positive lymph nodes, level IV/V nodal disease, and/or lymphovascular invasion. We assessed predictors of aCRT use and covariables impacting overall survival. RESULTS: aCRT was commonly used for both human papillomavirus (HPV)-positive (62.0%) and HPV-negative (64.3%) patients with OPSCC. Higher N stage, level IV/V neck disease, and younger age strongly predicted aCRT utilization. There was no significant survival benefit associated with aCRT vs aRT in HPV-positive (hazard ratio [HR], 0.93; 95% confidence interval [CI], 0.62-1.38; P = .71) or HPV-negative (HR, 0.75; 95% CI, 0.51-1.10; P = .15) disease. CONCLUSIONS: Despite high rates of utilization, aCRT is not associated with better survival vs aRT for OPSCC with intermediate-risk features, including HPV-negative tumors.