Objective: To investigate the value of fluorescence in situ hybridization (FISH) examination of urine exfoliative cells in the diagnosis of urinary bladder neoplasms.
Methods: The urine samples were collected from 100 patients with suspected urinary bladder neoplasms and 20 normal control subjects. Both FISH examination and cytology study of urine exfoliative cells were conducted with each sample. The specificity and sensitivity of FISH and cytology were analyzed on the basis of bladder biopsy histology.
Results: The sensitivity of FISH examination of bladder malignant tumor was 93.5% (87/93), which was much higher than that of cytology (49.5%, 46/93). Biopsies confirmed 88 cases of urothelial carcinoma among the 100 suspected patients, with 46 high grade tumors and 42 low grade tumors; 30 cases of high stage (T(2-4)) and 58 cases of low stage (T(a-1)). The sensitivity of FISH examination of urothelial carcinoma was 94.3%, which was much higher than that of cytology (52.3%). FISH examination was significantly more sensitive than cytology for low grade and low stage urothelial carcinoma, as well as for rare non-urothelial malignancies (P < 0.05). The specificity of FISH and cytology of bladder malignancies was 92.6% (25/27) and 96.3% (26/27), for urothelial carcinoma was 81.3% (26/32) and 96.9% (31/32), respectively.
Conclusion: FISH shows high sensitivity and relatively high specificity for the detection of urinary bladder neoplasms, especially for the diagnosis of low grade urothelial carcinoma and non-urothelial malignancies, which were difficult to be detected by cytology.