The newly developed UroVysion fluorescence in situ hybridization (FISH) probe was applied to urine specimens from 19 patients being monitored for recurrence of bladder cancer. The results for the multi-target DNA FISH assay were compared with independent analyses of urine cytology and flexible cystoscopy. Patients with tumors identified through the cystoscopy exam were biopsied and/or underwent surgery. In 12 patients with normal cytoscopy, cytology and FISH were also normal. Therefore, the specificity of these two tests was 100%. In 7 patients, a tumor was diagnosed by cystoscopy, and 3 of them had abnormal urine cytology while 6 of them had an abnormal result in the FISH assay. Accordingly, the sensitivity was 43% for the cytology and 87% for the FISH test. Interestingly, a pT1G3 tumor in a bladder diverticulum was not detected by cytology or the FISH test. These results agreed with a large series previously published using similar FISH probes and support the proposal for a multicenter trial to confirm the usefulness of the UroVysion probe as a screening tool to select patients for cystoscopy.