Surveillance of urothelial carcinoma of the urinary bladder (UBC) patients with respect to tumour recurrence and invasiveness is crucial for therapy and prognosis. Therefore, evaluation of non-invasive methods to monitor tumour progression is of high clinical interest. The study was aimed at investigating urinary concentrations of tenascin-C splicing domains for their value as tumour surveillance markers.Urinary concentration of B and C domain containing tenascin-C (Tn-C) was analysed by ELISA technology in 104 UBC patients, 11 patients with cystitis and 15 healthy donors as control. The investigation was supplemented by Tn-C immunohistochemistry and Western blotting.A statistically significant increase in urinary concentrations of both Tn-C B and C domain with tumour progression could be evidenced. A concordant tumour-associated enhanced protein deposition in the carcinoma stroma could be demonstrated by immunohistochemistry in invasive UBC. Western blotting reveals proteolytic fragmentation of urinary Tn-C.In summary, detection of Tn-C splicing domains in urine is suggested as a marker for the surveillance of UBC recurrence and invasiveness.