Survival outcomes for postoperative chemoradiation in intermediate-risk oral tongue cancers

Background: The survival outcomes for surgery + postoperative radiotherapy (S+RT) or surgery + postoperative chemoradiation (S+CRT) was compared in patients having oral tongue cancers with intermediate-risk pathological features. Methods: Using the National Cancer Database (NCDB), overall survival (OS) for S+RT or S+CRT was estimated using the Kaplan-Meier methods and Cox proportional hazard models in the entire population (n = 2803) and in a propensity-matched cohort (n = 1136). Results: The 3-year OS was 73.3% for S+CRT versus 66.7% for S+RT (P =.02). The S+CRT improved the 3-year OS for patients with 2 or more involved metastatic lymph nodes (≥2 MLNs; P =.01) but not for patients with <2 MLNs (P =.73). Undergoing S+CRT improved the 3-year OS for patients with pathologic T classification (pT) pT3-pT4 disease (P =.01) but not for patients with pT1-pT2 disease (P =.18). Conclusion: Undergoing S+CRT was associated with improved survival for patients with tongue cancers with ≥2 MLNs and/or pT3-pT4 suggesting that specific intermediate-risk pathological features benefit from treatment intensification.