Prognostic Significance of Nondiagnostic Molecular Changes in Urine Detected by UroVysion Fluorescence In Situ Hybridization During Surveillance for Bladder Cancer

ObjectivesTo determine the outcomes for patients with nondiagnostic fluorescence in situ hybridization (FISH) (ie, <4 gains of chromosomes 3, 7, or 17 in ≤3 cells). FISH detects urothelial carcinoma and is especially beneficial in patients with negative or atypical urine cytology findings. A positive result is defined as a gain of ≥2 chromosomes (3, 7, or 17) in 4 cells, isolated loss of 9p21 in 12 cells, or isolated gains of only 1 chromosome in ≥10% of cells. Most FISH-positive patients will develop recurrent urothelial carcinoma within 1 year.MethodsWe compared the data from 149 patients with a nondiagnostic FISH result and ≥30 months of follow-up with the data from patients with a negative FISH result from the same period. The time to conversion to a positive FISH result or the development of a bladder tumor was recorded.ResultsPatients with nondiagnostic FISH results had significantly greater rates of progression to positive FISH findings or the development of a bladder tumor than did patients with negative FISH findings. Most progression occurred within 1 year. Patients with nondiagnostic FISH results and concurrent negative cytology and cystoscopy had a very low risk of developing recurrent disease, similar to that found with truly negative FISH results.ConclusionsNondiagnostic FISH results are related to a greater risk of progression to positive FISH results and tumor recurrence than those with negative FISH findings. However, after controlling for negative cytologic and cystoscopic status, a nondiagnostic FISH result does not appear to be an independent predictor of disease recurrence, and aggressive investigation is not warranted.