Evaluation of the UBC test in the urine of healthy individuals, patients with benign disorders and urinary bladder cancer.

Abstract

Using the UBC test, the specificity, sensitivity and prognostic information were evaluated in patients with recently diagnosed transitional cell carcinoma (TCC) and in a control group consisting of apparently healthy individuals and individuals with benign disorders. Frozen urine samples from the 485 individuals in the control group and 100 newly diagnosed TCC patients were analyzed with the UBC test, specific for epitopes on cytokeratin fragments released from the urothelial cells. All the samples were analyzed and corrected for creatinine. No significant concentration difference was found between males and females (p=0.65) and there was no age dependent relation. The median concentration for the entire control group was estimated at 3.7 microg/g and the 95th percentile was calculated at 53.0 microg/g. The apparently healthy individuals in the control group had a median value of 3.4 microg/g with a 95th percentile of 24.3 microg/g. An increased frequency of elevated UBC concentrations was found in some benign disorders e.g., anemia, thyroid disorders, diabetes mellitus, hyperlipemia, urosepsis and cystitis. Patients with superficial tumors exhibited a 66% sensitivity (at 95% specificity), and the UBC concentrations did not differ statistically (p=0.16) from those patients with muscle invasive lesions with a 52% sensitivity. When the UBC concentrations were related to histopathological grade, a significant concentration difference (p<0.004) was found between low grade tumors (sensitivity 41%) and high grade tumors (sensitivity 72%). Survival analysis showed that patient with muscle invasive tumors, high-grade tumors and high UBC concentrations have a significantly reduced survival (five-year survival was estimated to 30%, 35% and 30% respectively) compared to patients with superficial tumors, low-grade tumors or low UBC concentrations (five-year survival, 60%, 85% and 75% respectively). The UBC test showed good accuracy and repeatability. Clinically the test could assist in tumor grading and the detection of recurrent disease, which in turn could assist in treatment selection for the individual patient and possibly improve prognosis.