The efficacy of anti-PD–1 antibody treatment has been shown in numerous kinds of tumors, including Hodgkin’s lymphoma, esophageal and gastric tumors, small–cell lung cancer (SCLC), NSCLC, kidney, hepatocellular, bladder, head and neck, and breast cancers [25]. The gene discussed is PDCD1; the disease is non-small cell lung carcinoma.