A detailed analysis of mutations in the 10 ultra-mutated cases of bladder cancers with TMB above 30 mutations/MB discloses that, besides the above-mentioned sample with the likely oncogenic POLE P286R mutation, which also possesses a MSH2 likely oncogenic mutation, no other cases contain likely pathogenic mutations in MMR related genes or the proofreading polymerases (Table 4). This evidence concerns the gene MRC1 and urinary bladder carcinoma.