CD274 and cancer: Immune checkpoint inhibitors (ICIs) are antibodies that target programmed cell death–1 (PD-1) or programmed cell death ligand–1 (PD-L1) and have recently revolutionized treatment for various cancer types, particularly non–small cell lung cancer (NSCLC).1,2,3,4,5,6 To determine ICI treatment outcomes more accurately, clinical biomarkers are essential.