Since PD‐L1 is an immune checkpoint molecule that inhibits the activation of T cells by binding to PD‐1 expressed on CD8+ killer T cells,21 anti‐PD‐L1 antibody therapy has been successfully used as an immunotherapy agent for various cancers, including melanoma and NSCLC.22, 23. This evidence concerns the gene CD8A and non-small cell lung carcinoma.