Adjuvant chemoradiation does not improve survival in elderly patients with high-risk resected head and neck cancer

Objectives/Hypothesis: Randomized trials have demonstrated that adjuvant chemoradiotherapy (CRT) confers an overall survival (OS) benefit over adjuvant radiation therapy (RT) alone in patients with resected head and neck squamous cell carcinoma (HNSCC) with adverse pathologic features (positive surgical margins [SM+] and/or extracapsular extension [ECE]). Whether this OS benefit exists in an elderly population remains unknown. Study Design: Retrospective database study. Methods: Using the National Cancer Database, we identified 1,686 elderly patients (age ≥70 years) with resected HNSCC with SM+ and/or ECE, who received adjuvant CRT (491 patients, 29%) or adjuvant RT alone (1,195 patients, 71%) between 1998 and 2011. Three-year survival rates were estimated using the Kaplan-Meier method both before and after propensity score matching (PSM). Crude and adjusted hazard ratios (HR) with 95% confidence intervals (CI) were computed using Cox regression modeling. Results: Median follow-up was 23.5 and 42.8 months for all and surviving patients, respectively. Three-year OS was 50.7% and 44.4% among patients receiving adjuvant CRT and RT alone, respectively (P =.002). On multivariate analysis, there was no significant improvement in OS with adjuvant CRT relative to adjuvant RT alone (HR: 0.88, 95% CI: 0.73-1.06). Similarly, a PSM cohort showed no significant difference in the 3-year OS for patients receiving adjuvant CRT versus adjuvant RT alone (48.8% and 50.9%, respectively; P =.839). Conclusions: Although the addition of chemotherapy to adjuvant RT has been proven effective in randomized trials of patients with resected HNSCC with SM+ or ECE, it may be less efficacious in an elderly patient population treated outside of a controlled trial setting. Level of Evidence: 2c. Laryngoscope, 128:831–840, 2018.