The Role of Salvage Chemotherapy on Survival Outcomes Following Immune Checkpoint Inhibitor Therapy in Recurrent and/or Metastatic Head and Neck Squamous Cell Carcinoma.

Background/aim: Immune checkpoint inhibitors (ICIs) have demonstrated clinical efficacy in recurrent and/or metastatic head and neck squamous cell carcinoma (R/M HNSCC). However, it remains a matter of debate which patient populations derive clinical benefit from salvage chemotherapy (SCT) following disease progression after ICI therapy.

Patients and methods: This retrospective study included 97 patients with R/M HNSCC who received ICI therapy (nivolumab or pembrolizumab). Patients were classified into SCT (n=54) and non-SCT (n=43) groups after ICI failure. Survival outcomes, response rates, and clinical variables were compared between groups.

Results: The SCT group showed a significantly longer median overall survival (OS) compared to the non-SCT group (16.6 vs. 2.4 months, p<0.0001). These findings indicate that patients who received SCT had markedly better outcomes. Multivariate analysis identified SCT [hazard ratio (HR)=4.93, p<0.00001] and ECOG PS0,1 (HR=2.42, p=0.0257) as independent prognostic factors for OS. Patients treated with paclitaxel plus cetuximab (PTX + Cmab) had higher objective response rate (ORR) (50%) and disease control rate (DCR) (68.4%) compared to other regimens.

Conclusion: SCT after ICI failure significantly improves survival in R/M HNSCC, particularly when using PTX+Cmab. Patients who received SCT had substantially better outcomes than those who did not. ECOG PS and sarcopenia status should be considered in treatment selection.