To understand which factors contributed to the distinct prognosis of bladder cancer subtypes defined by genomic architectures, we compared the prevalence of 60 potential driver events (26 SMGs and 34 arm‐level SCNAs) between clusters A and B. We showed that four SMGs (CREBBP, FGFR3, HRAS, and NFE2L2) but none of the frequent arm‐level SCNAs had significantly higher prevalence of genetic aberrations in cluster B patients who had better prognosis than in cluster A patients (FDR < 0.1, Fig. 4A and Table S8). The gene discussed is CREBBP; the disease is urinary bladder cancer.