Evaluation of upper urinary tract tumors by FISH in Chinese patients

Abstract

Upper urinary tract tumor (UUTT) usually presents a high grade and stage, and recurs frequently. The aim of this study was to evaluate the utility of a fluorescence in situ hybridization (FISH) assay on chromosomes 3, 7, 9, and 17 as a reliable and noninvasive method for the diagnosis of Chinese patients with UUTT. Urine specimens from 50 patients with UUTT and 25 donors without evidence of urothelial tumors were analyzed by cytology and FISH. Voided urine samples from 20 normal individuals were used to establish the cut-off values for FISH assay. The McNemar test was applied for sensitivity and specificity. The overall sensitivity of FISH was statistically significantly greater than that of cytology (84.0 vs. 40.0%, P = 0.000). The overall specificities of FISH and urine cytology were all 96.0% (P = 1.000). Polysomy in chromosomes 3, 7, and 17 were 38, 42, and 30%, respectively. Heterozygous and homozygous loss of the p16 locus was found in 36 and 32%, respectively. FISH analysis performed on cells collected from voided urine is feasible, and FISH could prove to be a reliable and less invasive ancillary test and improve the sensitivity of urine cytology in the diagnosis of UUTT.