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).