Outcomes and Biomarkers of Immune Checkpoint Inhibitor Therapy in Patients with Refractory Head and Neck Squamous Cell Carcinoma: KCSG HN18-12

Purpose This study was conducted to determine the effectiveness of immune checkpoint inhibitors (ICIs) in recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC) after platinum-containing chemotherapy. We also identified clinical biomarkers which may be predictive of patient prognosis. Materials and Methods We analyzed 125 patients with R/M HNSCC who received ICIs, retrospectively. Overall response rate (ORR) was the primary study outcome. Overall survival (OS) and progression-free survival (PFS) were the secondary study outcomes. Results The patients received anti-programmed cell death protein-1 (PD-1) (n=73, 58%), anti-programmed death-ligand 1 (PD-L1) (n=24, 19%), or a combination of anti-PD-1/PD-L1 and anti-cytotoxic T-lymphocyte antigen 4 (n=28, 22%). The median age was 57 years (range, 37 to 87). The location of the primary tumor was in the oral cavity in 28% of the cases, followed by oropharynx (27%), hypopharynx (20%), and larynx (12%). The ORR was 15% (19/125). With 12.3 months of median follow-up, median PFS was 2.7 months. Median OS was 10.8 months. A neutrophil-to-lymphocyte ratio (NLR) > 4 was significantly associated with poor response to ICIs (odds ratio, 0.30; p=0.022). A sum of the target lesions > 40 mm (hazard ratio [HR], 1.53; p=0.046] and a NLR > 4 (HR, 1.75; p=0.009) were considered to be predictive markers of short PFS. A poor performance status (HR, 4.79; p < 0.001), a sum of target lesions > 40 mm (HR, 1.93; p=0.025), and an NLR > 4 (HR, 3.36; p < 0.001) were the significant predictors for poor survival. Conclusion ICIs exhibited favorable antitumor activity in R/M HNSCC. Clinically, our findings can be used to recognize patients benefit from receiving ICI.

Automated summary

Our study found that ICIs exhibited favorable antitumor activity in treating head and neck squamous cell carcinoma, with certain clinical biomarkers like the sum of target lesions and neutrophil-to-lymphocyte ratio being predictive of patient prognosis.