Immune checkpoint inhibitors (ICIs), such as programmed cell death protein 1 (PD-1) or programmed death-ligand 1 (PD-L1) inhibitors, have become the standard of treatment for patients with advanced NSCLC because they have better clinical outcomes and possess favorable safety profiles compared with chemotherapy.1, 2, 3, 4, 5, 6 ICIs induce durable clinical responses; however, these are usually limited to a few patients receiving the treatment. The gene discussed is PDCD1; the disease is non-small cell lung carcinoma.