The expression of genes encoding immune checkpoint molecules, such as programmed cell death ligand 1 (PD‐L1), programmed cell death 1 (PD‐1), cytotoxic T‐lymphocyte antigen (CTLA)‐4, and CD8A, which is a marker of tumor‐infiltrating lymphocytes, was investigated. This evidence concerns the gene PDCD1 and neoplasm.