ICIs represented by programmed cell death protein 1 (PD-1) inhibitors and programmed cell death protein ligand 1 (PD-L1) inhibitors have demonstrated enduring, favorable objective responses in patients diagnosed with both non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) (5, 6). The gene discussed is PDCD1; the disease is non-small cell lung carcinoma.