IHC analysis of B7-H4, PD-L1, CD3, CD4, and CD8 was performed using a tissue microarray [94 HNSCC, 94 adjacent squamous intraepithelial neoplasia (SIN), and 69 adjacent normal oral mucosa (NOM) samples]. This evidence concerns the gene VTCN1 and squamous cell intraepithelial neoplasia.