Blocking antibodies that target programmed cell death 1 (PD-1) or programmed cell death protein ligand 1 (PD-L1) have been approved for the treatment of cancer and have significantly improved the outcomes of various advanced cancers, including non-small cell lung cancer (NSCLC) [1,2,3,4,5]. The gene discussed is PDCD1; the disease is non-small cell lung carcinoma.