As we had previously observed the positive prognostic effect of CD45RO + TILs in breast cancer [15], in the current study the expression pattern of PD-1, PD-L1, and CD45RO + immune cells and their relevance to clinicopathological features of disease were evaluated by immunohistochemical staining of the HNSCC tumor tissues. Here, CD274 is linked to head and neck squamous cell carcinoma.