Urinary calprotectin: a new diagnostic marker in urothelial carcinoma of the bladder

Purpose Recently, a proteomic study of sera from patients with bladder cancer identified S100A8 and S100A9 as tumor-associated proteins. The present cross-sectional study investigates whether calprotectin, the heterodimer of S100A8/S100A9 may serve as a urinary biomarker for the detection of urothelial bladder cancer. Methods Urinary calprotectin concentrations were assessed in a population of 181 subjects including 46 cases of bladder cancer. 41 cases of renal cell cancer, 54 cases of prostate cancer, and 40 healthy subjects served as control. Acute kidney injury, urinary tract infection, previous BCG-treatment and secondary transurethral resection of the bladder tumor were defined as exclusion criteria. Assessment was performed by enzyme-linked immunosorbent assay and immunohistochemistry detecting calprotectin. Results Median calprotectin concentrations (ng/ml) were significantly higher in patients with bladder cancer than in healthy controls (522.3 vs. 51.0, p