The fibroblast growth factor receptor 3 (FGFR3) mutation is a strong indicator of superficial bladder cancer with low recurrence rate.

We analyzed the possible prognostic value of the recently discovered fibroblast growth factor receptor 3 (FGFR3) mutations in bladder cancer. A FGFR3 mutation was found in 34 of 53 pTaG1-2 bladder cancers, whereas none of the 19 higher-staged tumors had a mutation (P < 0.0001). In 57 patients with superficial disease followed prospectively by cystoscopy for 12 months, 14 of 23 patients in the wild-type FGFR3 group developed recurrent bladder cancer compared with only 7 of 34 patients in the mutant group (P = 0.004). The recurrence rate per year was 0.24 for the FGFR3 mutant tumors and 1.12 for tumors with a wild-type FGFR3 gene. In addition, FGFR3 mutation status was the strongest predictor of recurrence when compared with stage and grade (P = 0.008). This is the first mutation in bladder cancer that selectively identifies patients with favorable disease characteristics. Our results suggest that the frequency of cystoscopic examinations can be reduced considerably in patients with FGFR3-positive tumors.