Clinical Study on the value of NMP22 in the monitoring of recurrent bladder cancer

Objective To assess the clinical value of the NMP22 Bladder Chek test, which is a qualitative test, and to compare it with voided urine cytology for the detection of recurrent bladder cancer. Methods The urine samples before a cystoscopic examination were collected in a total of 117 patients with a history of superficial transitional cell carcinoma of the bladder. Urine samples were assayed for the presence of NMP22 using the NMP22 Bladder Chek test and cytology was performed by a cytopathologist. Selected patients underwent a biopsy, with appropriate additional therapy. Results The two tests were compared with the results of pathology, which was retained as the gold standard. For positive biopsies, the results of the NMP22 test and cytology were also correlated with the tumor stage and grade. Results Of the 39 recurrences detected by cystoscopy, the NMP22 test was positive in 33 cases and cytology in 16 cases. The sensitivity of the NMP22 test was 84.6%, which was significantly higher than that of cytology (41.2%). In particular, for low-risk tumors it was eight times more sensitive than cytology. The specificities of the NMP22 test and cytology were 74.2 and 92.1%, respectively. Combining the two tests increased overall sensitivity to 91%. Conclusions The NMP22 test is superior to cytology for all grades and stages in the detection of recurrence in patients with a history of superficial bladder cancer. Our study indicates that the NMP22 test can be used as a substitute for urine cytology. The NMP22 test cannot replace cystoscopy, but it can be used as an adjunct to cystoscopy in the surveillance of patients with superficial bladder cancer.