Quantitative detection of human complement factor H-related protein in transitional cell carcinoma of the urinary bladder

Objective: The purpose of th is study was to assess a new quantitative urinary tumor marker for transitional cell carcinoma of the urinary bladder (TCC), human complement factor H-related protein (hCFHrp, BTA TRAK(TM)). Methods: Urine samples of 298 individuals (76 healthy volunteers, 118 patients with benign urologic disorders, 104 patients with histologically proven bladder cancer) were examined for the presence of hCFHrp. Samples of all patients were obtained prior to therapy. Results: In comparison to healthy volunteers, patients with TCC had significantly higher urinary levels of hCFHrp (117.60 vs. 2.05 U/ml; p < 0.001). HCFHrp levels were positively correlated with tumor grade and stage. Patients with invasive TCC had significantly higher levels of hCFHrp than patients with superficial TCC (p = 0.001). Marker levels in superficial bladder cancer at high risk of tumor progression (pT1G3) were significantly higher as compared to low and intermediate grade superficial cancers. Elevated levels of hCFHrp were also found in patients with benign urologic disorders (median: 72.65 vs. 117.60 U/ml in cancer patients). Using a cutoff of 17.1 U/ml, hCFHrp had a sensitivity of 72.1% and, due to a high rate of false-positive determinations in patients with benign urologic disorders, a total specificity of 50.5%. Conclusions: HCFHrp (BTA TRAK(TM)) is a sensitive test for detection of bladder cancer and for identification of patients at high risk. Due to a high rate cf false-positive results in patients with benign urologic diseases, the test should not be used in an unselected population.