IFNG and head and neck squamous cell carcinoma: Of the 23 HNSCC samples analyzed, 15 (65.2%) had sufficient colony formation of epithelial cells (mean CFec ≥ 4/well), allowing assessment of the effects of pembrolizumab, cetuximab, and pembrolizumab + cetuximab and their combination with IFN-γ (Figures 1A, B).