PDCD1 and non-small cell lung carcinoma: The U.S. Food and Drug Administration has approved pembrolizumab (a PD-1 inhibitor) as a first-line therapy for tumors with a PD-L1 tumor proportion score ≥ 1% in NSCLC, cemiplimab (also a PD-1 inhibitor) for patients with PD-L1 expression ≥ 50%, and atezolizumab (a PD-L1 inhibitor) for patients with high PD-L1-expressing metastatic NSCLC [5].