Among patients with R/M HNSCC without PD-L1 selection, nivolumab was most likely to rank first for OS with a cumulative probability of 64.17%.Pem-chemo ranked first for PFS (69.42%) and ORR (35.06%), while pembrolizumab monotherapy was most likely to rank first for grade ≥3 AEs (56.42%). This evidence concerns the gene CD274 and head and neck squamous cell carcinoma.