UPK3A: a Promising Novel Urinary Marker for the Detection of Bladder Cancer

Objectives: Current methods for reliable detection of bladder cancer have some limitations. Finding better noninvasive methods for detection of bladder cancer is an important topic in urology. We want to evaluate prospectively the early detection power of human uroplakin 3 A (UPK3A) for bladder cancer.

Methods: Urine samples were obtained from 32 healthy volunteers, 44 patients with benign urological disorders and 122 patients with bladder cancer. The urine UPK3A levels were quantified by enzyme-linked immunosorbent assay. All the samples were also tested with NMP22 test and cytology examination.

Results: The urinary UPK3A levels are uniformly elevated in bladder cancer patients than in those of normal volunteers and patients with benign urological disorders, and the differences in the mean urinary UPK3A levels of bladder cancer patients and those of normal individuals or benign urological disorders are statistically significant (P <.01). The receiver operating characteristic (ROC) curve of UPK3A showed an excellent area under the ROC curve of 0.907. In this study, the optimal combination of sensitivity and specificity were determined as 83% and 83%, for a cut-off value of absorbance unit 0.0685, respectively. The sensitivity of urine UPK3A, NMP22, and cytology for detecting bladder cancer were 83%, 58%, and 64%, respectively, whereas specificity was 83%, 75%, and 82%, respectively.

Conclusions: We conclude that individuals with bladder cancer have higher UPK3A values. Our data suggest that urine measurement of UPK3A is a sensitive marker for the detection of bladder cancer. However, it needs further studies in larger cohorts.