Usefulness of NMP22 BladderChek for the Diagnosis and Monitoring of Bladder Cancer

BACKGROUND: As bladder cancer is a superficial tumor with frequent recurrences, early detection and confirmation of recurrence are important. We evaluated the usefulness of NMP22 BladderChek (NMP22BC) for the diagnosis and monitoring of bladder cancer. METHODS: From July to December 2004, we enrolled in the study 670 patients who visited the urology clinic in Ewha Womans University, Dongdaemun Hospital with hematuria or dysuria and were tested with NMP22BC. We also performed the NMP22BC and BTA stat tests simultaneously in 21 patients and interference test in 10 patients. RESULTS: NMP22BC tests were negative in 97% of the patients who had been cured of bladder cancer and were positive in 95% of the patients with recurred bladder cancer. The diagnostic sensitivity, specificity, positive and negative predictive value, and efficiency were 95.0%, 91.5%, 25.7%, 99.8%, and 91.6%, respectively, with 8.5% false positive and 5% false negative rates. Fifty-five patients showed false positive in the NMP22BC test, the main cause of which was the presence of WBCs in urine. There was a good agreement between the NMP22BC and BTA stat tests (kappa agreement value, 0.5; P=0.008). According to the interference test, two patients with more than 3+ in leukocyte esterase results showed false positive in the NMP22BC test. CONCLUSIONS: NMP22BC test was simple to perform, rapid to produce the results, and useful in diagnosing a bladder cancer recurrence; the test shows a high efficiency with a high sensitivity, specificity, negative predictive value, and low false negative rate.