For bladder cancer, although the Ventana PD‐L1 assays have been FDA approved as biomarkers for atezolizumab (https://www.fda.gov/Drugs/InformationOnDrugs/ApprovedDrugs/ucm501878.htm) and durvalumab (https://www.fda.gov/Drugs/InformationOnDrugs/ApprovedDrugs/ucm555930) treatments, there is some degree of ambiguity in data from clinical studies for the correlation of PD‐L1 expression to therapeutic response and it has limited negative predictive value 60, 61, 63, 64, 65, 66, 69, 70, 71, 73, 74, 75. This evidence concerns the gene CD274 and urinary bladder cancer.