CD274 and non-small cell lung carcinoma: Four of such PD-L1 immunohistochemistry assays are currently recognized by the United States Food and Drug Administration (US FDA) as companion diagnostics: (1) Dako 22C3 for pembrolizumab for a range of solid tumors [20,21,22,23,24]; (2) Dako 28-8 for ipilimumab and nivolumab in non-small-cell lung cancer (NSCLC) [25]; (3) Ventana SP142, and (4) Ventana SP263 for atezolizumab in urothelial carcinoma, triple-negative breast cancer or NSCLC [26,27,28,29].