To interrogate the nature of ERCC2 mutations more deeply in bladder cancer, we assembled a multiinstitutional cohort of bladder cancer cases (n = 2,012; Supplemental Figure 1A; supplemental material available online with this article; https://doi.org/10.1172/JCI186688DS1) that represents the largest clinically and/or genomically annotated database of ERCC2-mutant cases analyzed to date. This evidence concerns the gene ERCC2 and urinary bladder cancer.