Incurable locoregional disease is a strong poor prognostic factor in recurrent or metastatic squamous cell carcinoma of the head and neck.

Background: Distant metastasis is a poor prognostic factor in recurrent/metastatic squamous cell carcinoma of the head and neck. However, limited information on the prognostic impact of locoregional disease is available, despite its life-threatening features. We investigated the prognostic impact of incurable locoregional disease and distant metastasis in recurrent/metastatic squamous cell carcinoma of the head and neck.

Methods: We retrospectively analyzed 156 patients with recurrent/metastatic squamous cell carcinoma of the head and neck who received palliative chemotherapy between August 2006 and December 2019.

Results: The median follow-up time for all censored patients was 12.1 (range 1.9-63.5) months. The median overall survival was 12.4 (95% confidence interval 10.1-15.1) months. Incurable locoregional disease (hazard ratio: 2.31, P = 0.007), liver metastasis (hazard ratio: 2.84, P = 0.006), disease-free interval > 13 months (hazard ratio: 0.51, P = 0.041), cetuximab use (hazard ratio: 0.59, P = 0.007), and immune checkpoint inhibitor use (hazard ratio: 0.56, P = 0.006) were associated with prognosis. The number of distant metastatic sites was not associated with overall survival (1-2: hazard ratio: 0.60, P = 0.16; 3-4: hazard ratio: 1.34, P = 0.50). Patients with incurable locoregional disease had more life-threatening events than those with curable locoregional disease.

Conclusion: The presence of incurable locoregional disease had a significant prognostic impact, whereas the number of distant metastatic sites had no prognostic impact. Liver metastasis was a poor prognostic factor for recurrent/metastatic squamous cell carcinoma of the head and neck.