Utility of Fluorescence In Situ Hybridization (FISH) to Sub-Classify Low-Grade Urothelial Carcinoma for Prognostication

BACKGROUND Fluorescence in situ hybridization (FISH) is used widely to detect cancer levels, but its value in urothelial carcinoma remains unclear. The aim of this study was to use FISH to examine the urine specimens of low-grade urothelial carcinoma (UC) patients to determine the possibility of sub-classifying the prognosis of UC. MATERIAL AND METHODS We diagnosed 107 patients with low-grade UC using a UroVysion kit to detect chromosomes 3, 7, 17, and P16 in the urine. An average 46.6-month follow-up completed in January 2016 combined with the clinical follow-up data were evaluated with Spearman's correlation analysis to analyze the aberration of chromosomes in relation to the prognostication. Univariate and multivariate analysis using the Mantel-Cox log-rank test for overall, cancer-specific, and disease-free survival were used to determine the prognostic significance of CSP7/CSP17 and CSP3/GLPp16. RESULTS In the 107 samples, 84 showed positive reaction in the FISH test. Furthermore, CSP7/CSP17 was found to be significantly related with age, tumor size, T stage, and tumor numbers, but not in CSP3/GLPp16. In addition, Kaplan-Meier analysis and Cox proportional hazards regression revealed a significant negative correlation between CSP7/CSP17 and survival, while CSP3/GLPp16 showed no significantly differences. CONCLUSIONS CSP7/CSP17 positivity on FISH test appears to play a critical role in low-grade UC and may be considered as a high-risk and prognosis factor.