Survival outcomes and optimal candidates for primary tumor resection in head and neck squamous cell carcinoma with distant metastasis at initial diagnosis.

Introduction: The incidence of distant metastasis for head and neck squamous cell carcinoma (HNSCC) is low, and there is scant evidence to prove the prognostic value of primary tumor resection (PTR) in these cases. This study aimed to assess the survival outcomes and identify optimal candidates for PTR in HNSCC with distant metastasis at initial diagnosis.

Materials and methods: Patients initially diagnosed with metastatic HNSCC between 2010 and 2021 were collected from the Surveillance, Epidemiology, and End Results (SEER) database. A Cox proportional hazards regression model was used to assess prognostic factors for survival. Survival outcomes were calculated with the Kaplan-Meier method and compared by the log-rank tests.

Results: A total of 2740 patients with newly metastatic HNSCC were extracted, among whom 403 (14.7%) received PTR. Lung, distant lymph node (DLN), and bone were the most common sites of metastasis. PTR was associated with improved overall survival (OS) and cancer-specific survival (CSS) in the whole cohort (HR = 0.653, 95%CI 0.551-0.774 for OS; HR = 0.621, 95%CI 0.515-0.748 for CSS). When focusing on different metastatic patterns, PTR conferred a significant survival benefit for patients with bone, lung, liver and DLN involvement (all p < 0.05). Among patients with single-organ metastases, those who underwent surgical resection showed substantially favorable OS and CSS (both p < 0.001). Furthermore, subgroup analyses suggested that patients with younger age (< 65 years), low histological grade (grade I-II), and stage N0-2 disease might benefit from PTR.

Conclusion: This study demonstrated that PTR exhibited a favorable prognostic value and held promise for the intervention of carefully-selected patients with metastatic HNSCC, although long-term prospective studies were warranted.