FGFR3 and urinary bladder cancer: Though seen most commonly in bladder cancer (20%–70% in high‐grade and low‐grade bladder cancers, respectively), FGFRalt occurs at various frequencies across a wide range of malignancies [2, 3, 5, 6, 7, 8, 9], including non–small‐cell lung cancer (NSCLC; FGFR3/2, ~3%) [6, 7] and cholangiocarcinoma (CCA; 10%–16%, FGFR2 fusion, ~45%) [8, 9, 10].