Fluorescence In Situ Hybridization in Urine Samples (UroVysion Kit)

Cystoscopy is considered the standard approach to the diagnostic workup of urinary symptoms. It has high sensitivity and specificity for papillary tumors of the bladder but low sensitivity and specificity for flat lesions. It is also expensive and may cause discomfort and complications. Urine cytology, in contrast, has the advantage of being a noninvasive test with high specificity but suffers from low sensitivity in low-grade and early-stage tumors, possibly due to the low number of exfoliated cells in urine. Numerous new noninvasive tests have been proposed. Among these, fluorescence in situ hybridization (FISH) has been studied for long time and in 2005 UroVysion Bladder Cancer Kit (UroVysion Kit) (Abbott/Vysis) received FDA approval for initial diagnosis of bladder carcinoma in patients with hematuria and subsequent monitoring for tumor recurrence in patients previously diagnosed with bladder cancer. The UroVysion Kit is designed to detect aneuploidy for chromosomes 3, 7, 17, and loss of the 9p21 locus by FISH in urine specimens from symptomatic patients, those with hematuria suspected of having bladder cancer. Here, the approach for FISH assay by using UroVysion Bladder Cancer kit according to manufacturer's instructions is described.