CD274 and head and neck squamous cell carcinoma: Programmed death ligand-1 (PD-L1), combined positive score (CPS), tumor mutation burden (TMB), and neutrophil-to-lymphocyte ratio (NLR) are being evaluated individually or in complex models to stratify HNSCC patients and identify who would benefit the most from ICI [1,2,3,4,5,6,7,8].