Diagnosis of urothelial carcinoma from urine

Urine cytology is the most widely used noninvasive test to detect urothelial tumors. However, it is limited by its low sensitivity. On the other hand, cystoscopy is the gold standard procedure to follow patients with a history of bladder cancer but this test is invasive and costly. Therefore, there is a real need to develop new tests that can be used in bladder cancer surveillance. Several soluble and cell-based markers have been developed and most of them improve the sensitivity of cytology but the specificity is invariably decreased. Of the cell-based tests, two obtained Food and Drug Administration approval. ImmunoCyt/uCyt is a fluorescent test that uses three monoclonal antibodies and UroVysion is an in situ hybridization test, which uses four different probes to different chromosomes. Both tests have a high sensitivity to detect cancer cells and can help to predict urothelial cancer recurrence. ImmunoCyt/uCyt is somewhat better at detecting low-grade tumors but UroVysion is not affected by prior BCG treatment. However, both tests use fluorescent dyes, are time-consuming and require trained personnel. Because of their high negative predictive value, both tests may help the urologist to postpone a number of cystoscopies, especially in patients with low-risk urothelial cancer.