Comparison of urine cytology and fluorescence in situ hybridization in upper urothelial tract samples

Abstract

BACKGROUND:The cytologic diagnosis of urothelial carcinoma (UC) of the upper urothelial tract (UT) is challenging.Using the UroVysion probe set adds diagnostic value for the detection of bladder cancer in voided urine. In instrumented Biopsy confirmation of UTUC in 21 patients was considered the gold standard. RESULTS: Cytology alone was found to be poorly sensitive (38%) but highly specific (89%) for the detection of UTUC. FISH was found to increase the sensitivity of cytology and decrease specificity. Tetrasomy FISH resulted in many false-positive cases. Other false-positive FISH results were likely due to the presence of bladder cancer cells contaminating the UT specimen. CONCLUSIONS: Caution should be used when evaluating instrumented urine specimens of the UT from patients with a previous history of bladder carcinoma, and tetrasomy FISH results should not be interpreted as abnormal because it significantly lowers the specificity of the test. The combination of cytology and FISH appears to have good specificity while maintaining good sensitivity in evaluating UTUC when using modified scoring criteria for the appropriate patient population. Cancer (Cancer Cytopathol) 2014;122:459-67.

Prospective evaluation of FISH for detecting upper tract urothelial carcinoma in voided urine specimens

“…This difference may be due to the fact that the majority of patients in the cohort analyzed by Huang et al (17) exhibited high-grade UTUCs, for which the FISH assay has higher sensitivity than for low-grade tumors (17,20). The sensitivity of FISH for the detection of UTUC identified in the present study was similar to that reported by Gruschwitz et al (21), but higher than that reported by Reynolds et al (9). There is a possible reason for this difference.…”

“…Suspicious cytology was defined as those samples that contained cells with morphologies that could not be clearly classified as tumor or normal cells. Histopathological classification was performed according to the Union for International Cancer Control criteria (8,9).…”

“…However, patients usually do not accept collecting clean catch urine, but would rather collect voided urine, particularly in China (7,19). In addition, reference standards of positive FISH are based on the diagnostic criteria of bladder cancer (9). However, exfoliative cells of the upper ureter or renal pelvis are present in low quantities in voided urine and are susceptible to contamination by bladder cells.…”

“…To date, only a limited number of sensitively accepted markers have been applied to detect urinary tumors, including ImmunnoCyt™/uCyt+™ and fluorecence in situ hybridization (FISH) technology (7)(8)(9). FISH technology is generally used for the diagnosis of bladder cancer in voided urine in China, due to its high sensitivity and specificity, but its use for detecting UTUCs is limited, due to its low reliability (10).…”

Prospective evaluation of fluorescence in situ hybridization for diagnosing urothelial carcinoma

“…Bubendorf et al (32) suggested that the detection of ≤4 tetrasomic cells in each sample should be considered normal in order to improve diagnostic value. Concurrently, Reynolds et al (33) demonstrated that FISH had improved sensitivity vs. cytology, but decreased specificity due to a greater number of false-positive results. Considering the lack of validation of the UroVysion criteria in the Chinese population, the threshold was determined by performing FISH assays on samples from healthy donors.…”