Fluorescence in situ hybridization for detecting upper urinary tract tumors - A preliminary report

OBJECTIVES To evaluate fluorescene in situ hybridization (FISH) in voided urine specimens and selective upper urinary tract washings obtained from patients with suspected transitional cell cancer of the upper urinary tract (UT-TCC). METHODS A total of 16 patients with suspected UT-TCC were included in the study. All patients underwent urinary tract imaging. Endoscopy was also performed. Voided urine specimens from all patients and ureteral washings were subjected to cytologic examination and FISH analysis (UroVysion probe set). If indicated, surgery (nephroureterectomy or ureterectomy) was performed. RESULTS Of the 16 patients, 9 (56.25) were diagnosed with UT-TCC. None of the remaining patients was diagnosed with UT-TCC after a mean follow-up of 21.3 months (median 20, range 11 to 36). For FISH analysis, the sensitivity was 87.5% and specificity 80%. FISH analysis was not possible in 1 patient with UT-TCC because of an insufficient number of cells. For cytology, the sensitivity was 60% and specificity 80%. In patients with UT-TCC, the cytologic findings were inconclusive (atypia of uncertain significance) in 4 patients (44.4%). In contrast to the cytology findings, all results of the FISH analysis of the upper urinary tract washings matched those of the voided urine samples. CONCLUSIONS Our preliminary data suggest that FISH analysis of voided urine might be a useful ancillary test in the detection of UT-TCC with excellent sensitivity and specificity. If confirmed in larger studies, FISH might conditions to a more reliable and less-invasive diagnostic approach to UT-TCC.