The value of the preoperative FISH test in unscreened bladder cancer patients with TUR indications.

Patients with bladder cancer are still requiring close follow up with frequent cystoscopies. This study aims to assess the FISH analysis, as a procedure capable of highlighting the hidden features of a tumor and helping to individualize treatment tactics. The bladder washings of 50 primary bladder cancer patients were taken prior to TURB and analyzed with the commercial FISH assay UroVysion®. All patients were divided into groups according to the maximum stage and grade of the tumor. The sensitivity of the method was 81.5 %, 91.7 % and 100 % for the Ta, T1 and T2 stage groups, respectively. For the G1, G2 and G3 groups the sensitivity was 70 %, 100 % and 100 %, respectively. In addition, the rate of detecting genetically abnormal cells was significantly higher in the T2 stage compared to the Ta and combined Ta+T1 groups, as well as in the G3 group compared to the G1 and G2 groups. The mean signal number from each chromosome insignificantly increased with the stage and grade of the tumor. The detection of <40 % genetically abnormal cells predicted the absence of muscle invasion and a G3 tumor with more then 90 % reliability. The FISH method is highly sensitive in early bladder cancer detection and is able to predict the morphological character of a tumor even before surgery.