Predictive value of the FGFR3 mutation assay increases with multiple consecutive FGFR3-positive urine samples. Predictive value of the FGFR3 mutation assay increases with multiple consecutive FGFR3-positive urine samples. Kaplan-Meier analysis of proportion recurrence for patients included with an FGFR3-mutant tumor. X axis depicts the length of time being recurrence-free with consecutive FGFR3 urine results. Y axis depicts the proportion of recurrences detected. Tahlita C.M. Zuiverloon et al. Clin Cancer Res 2010;16:3011-3018 ©2010 by American Association for Cancer Research