Comparative evaluation of the BTAstat test, NMP22, and voided urine cytology in the detection of primary and recurrent bladder tumors

Objectives. This prospective study was undertaken to evaluate the diagnosti c efficacy of the BTAstat test and nuclear matrix protein (NMP22) compared with voided urine cytology (VUC) in the detection of primary and recurrent bladder cancer. Methods. A total of 147 patients provided a single voided urine sample for the BTAstat test, NMP22, and cytology prior to cystoscopy. Eighty-five of t hem had no bladder cancer history, whereas the remaining 62 were monitored for superficial bladder cancer. A group of 21 healthy age-matched volunteer s were also enrolled in the study. Results. Bladder cancer was confirmed histologically in 99 patients, of whi ch 62 had primary tumors and 37 had recurrent ones. The overall sensitivity and specificity were 71.7% and 56.5% for the BTAstat test, 62.6% and 73.9% for NMP22, and 38.4% and 94.2% for VUC. The optimal threshold value for NM P22 calculated with receiver operating characteristics curve, was 8 U/mL. B TAstat test was significantly more sensitive than VUC in detecting bladder cancer in all stage and grade subgroups, except GIII. On the contrary, NMP2 2 was significantly more sensitive than VUC only in stage Ta, grade I and I I patients. BTAstat test had higher but not significantly different sensiti vity than NMP22. Conclusions. Our data indicate a superiority of both BTAstat test and NMP22 over VUC in the detection of bladder cancer. Comparing BTAstat test with N MP22, the former proved to be more sensitive, whereas the latter was more s pecific. Ruling out diseases with potential interference can increase the o verall specificity of both tests. False-positive results of either test in patients followed up for bladder cancer seem to correspond to future recurr ences. UROLOGY 55: 871-875, 2000. (C) 2000, Elsevier Science Inc.