Current bladder tumor tests: Does their projected utility fulfill clinicalnecessity?

Purpose: We reviewed currently available bladder cancer tests in the contex t of the clinical expectations of a noninvasive bladder cancer test. Materials and Methods: We reviewed the literature on bladder cancer tests t hat are commercially available or have shown clinical usefulness and examin ed how each test compares with standard methods of bladder cancer diagnosis . Results: The clinical necessity for a noninvasive test for bladder cancer i s 2-fold, including the early detection of high grade bladder tumors before muscle invasion and monitoring tumor recurrence or new onset. An ideal non invasive test should be sensitive, specific, rapid, technically simple and have low intra-assay and interassay variability. Urine cytology has high sp ecificity but limited applicability due to its relatively low sensitivity a nd subjective nature. Hematuria detection by Hemastix* dipstick is sensitiv e but not specific for detecting bladder cancer. Molecules associated with bladder tumor growth and progression may serve as a basis for designing non invasive diagnostic tests. The Food and Drug Administration approved BTA St at and BTA TRAK dagger tests, which detect human complement factor H and a related protein in urine, have 60% to 80% sensitivity and 50% to 70% specif icity (lower in symptomatic patients) for bladder cancer. The Food and Drug Administration approved NMP22 double dagger test, which measures the level of nuclear mitotic apparatus protein in urine, has 50% to 100% sensitivity and 60% to 90% specificity. Accu-Dx detects fibrin degradation products, f ibrin and fibrinogen in urine, although this test is no longer commercially available. The Immunocyt parallel to test combines cytology with an immuno fluorescence technique to improve the sensitivity of cytology for detecting low grade tumors. The telomeric repeat amplification protocol assay for te lomerase in exfoliated cells has 70% to 86% sensitivity and 60% to 90% spec ificity for bladder cancer. However, the low stability of telomerase in uri ne affects its sensitivity. The hyaluronic acid and hyaluronidase (HA-HAase ) test, which measures the urinary level of hyaluronic acid and hyaluronida se, has 90% to 92% sensitivity and 80% to 84% specificity for bladder cance r. Quanticyt karyometry evaluates nuclear shape and DNA content of exfoliat ed cells to detect bladder cancer. The list of bladder tumor markers is gro wing rapidly and large multicenter trials are essential to assess their use fulness. Conclusions: Although currently noninvasive bladder cancer tests cannot rep lace cystoscopy, some have shown a promise of being clinically useful. One or a combination of these tests-markers may prove to be a prostate specific antigen for bladder cancer provided that patients and, more importantly, c linicians accept it.