Long‐Term Survival Outcomes of Concurrent Chemoradiotherapy for Postoperative High‐Risk Salivary Gland Carcinomas

Background This study evaluated the long‐term survival outcomes of concurrent chemoradiation (CCRT) for high‐risk salivary gland carcinomas (SGCs). Method Postoperative patients with high‐risk SGCs, other than adenoid cystic carcinoma (ACC), with T3‐4/N1‐3M0 disease were enrolled. This study included a cohort of 55 patients who received CCRT, derived from a prospective phase II trial, and a retrospective cohort of 61 patients treated with RT alone. Results The median follow‐up for survivors was 54.1 months. In the subgroup analysis, patients without ENE treated with CCRT showed significantly better 5‐year OS (83.4% vs. 69.0%, p = 0.032), with a numerically higher 5‐year DFS (57.3% vs. 41.6%, p = 0.062). In the subgroup of patients with N0‐1 disease, those treated with CCRT showed a numerically higher 5‐year DFS (69.1% vs. 44.9%, p = 0.073) and OS (90.7% vs. 76.2%, p = 0.057). On multivariate analyses, CCRT significantly predicted superior DFS ( p = 0.021) and OS ( p = 0.004) for patients without ENE and superior DFS (p = 0.027) for patients with N0‐1 disease. Conclusion For postoperative high‐risk non‐ACC SGCs, CCRT was associated with improved long‐term survival outcomes in patients without ENE or with N0‐1 disease, which need further evaluation in randomized trials. However, for patients with ENE or N2‐3 disease, they may need alternative treatment strategies to enhance their prognosis. Trial Registration The prospective cohort analyzed in this study originated from the non‐ACC group enrolled in a phase 2 clinical trial (NCT02776163)