Elective neck dissection and adjuvant therapy in N0 major salivary gland cancer: An analysis of the SEER cancer database

PURPOSE: High-grade major salivary gland cancer is associated with poor prognostic outcomes, but the role for elective neck dissection (END) for improving survival in high-grade N0 major salivary gland cancer is under debate, especially in the context of planned adjuvant therapy. METHODS: We performed a secondary analysis of the SEER cancer database for all patients surgically treated for N0 major salivary gland cancer from 2000 to 2022. Our primary outcome was disease-specific survival (DSS), and our secondary outcome was overall survival. We generated multivariable Cox regression models to evaluate the association of END with survival outcomes. RESULTS: Across the study cohort of 1387 patients, END was independently associated with better DSS (adjusted HR: 0.49, 95% confidence interval (CI): 0.28, 0.83; p < 0.01) in high-grade N0 major salivary gland cancer, but not low-to-intermediate grade N0 major salivary gland cancer (adjusted HR: 0.82, 95% CI: 0.32, 2.08; p = 0.67). END alone (adjusted HR: 0.23, 95% CI: 0.05, 1.07; p = 0.06) or with adjuvant radiotherapy (adjusted HR: 0.42, 95% CI: 0.18, 1.00; p = 0.05) may improve DSS in high-grade T1/T2 N0 disease, while END with adjuvant radiotherapy may be necessary for T3/T4adisease, but these results were inconclusive and require validation. CONCLUSION: Surgeons may consider END in patients with high-grade N0 major salivary gland cancer but opt for regional surveillance in patients with low-to-intermediate grade disease. END with or without adjuvant radiotherapy may be considered in T1/T2 high-grade N0 major salivary gland cancers, but both modalities are likely necessary in T3/T4 disease; however, further confirmatory studies are needed.