Thus far, four PD-L1 assays have been approved by the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) for clinical use among urothelial carcinoma patients, i.e., based on the Dako 28-8 and 22C3 and the Vantana SP142 and SP263 monoclonal antibodies. The gene discussed is CD274; the disease is urothelial carcinoma.