The advent of immune checkpoint inhibitors (ICIs), particularly programmed cell death protein 1 (PD‐1) and programmed death‐ligand 1 (PD‐L1) inhibitors such as pembrolizumab, has substantially improved survival outcomes in advanced non‐small cell lung cancer (NSCLC), especially in patients whose tumors express high levels of PD‐L1 (tumor proportion score (TPS) ≥ 50%) and who lack driver mutations in EGFR or ALK [2, 3]. The gene discussed is PDCD1; the disease is lung cancer.