Urine concentration of nuclear matrix protein 22 for diagnosis of transitional cell carcinoma of bladder

The aim of this study was to determine the diagnostic value of urine nuclear matrix protein 22 (NMP22) level in detection of transitional cell carcinoma (TCC) of the bladder.

A total of 76 patients with newly-diagnosed or recurrent TCC and 75 controls without urinary tract disorders participated in this study. A urine sample was obtained for measurement of the NMP22 level using the enzyme-linked immunoabsorbent assay. The resulted values were evaluated in comparison with the results of pathologic examination.

A total of 76 patients with TCC of the bladder and 75 volunteers without TCC were enrolled in the study. The mean level of urine NMP22 had an increasing trend associated with tumor grade (P = .01) and tumor stage (P < .001). In participants without TCC, the mean urinary NMP22 level was 5.48 +/- 6.34 U/mL, while this value was 25.01 +/- 35.33 U/mL in patients with TCC of the bladder (P < .001). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of urine NMP22 for detection of TCC were 75.5%, 86.7%, 85.1%, 77.4%, and 80.8%, respectively. The sensitivity of NMP22 in detecting stage Ta tumors appeared to be low (31.3%), but for grade 1 tumors, the sensitivity was 66.7%.

Measurement of urine NMP22 is a noninvasive, highly sensitive, and specific method for detecting TCC of the bladder and estimating its grade and stage. Further studies can be helpful to determine whether it can be used in clinical practice.