Pre-clinical data suggest that FGFR3 mutations are exclusive to non-inflamed bladder cancers (~ 30% of tumors), a subgroup characterized by absence of CD8 tumor infiltrating lymphocytes (CD8 TILs), worsen prognosis, and lower chance of responding to PD-L1 blockade. This evidence concerns the gene FGFR3 and urinary bladder carcinoma.