To search for bladder squamous cell carcinoma markers that are released to the urine a blind and systematic analysis of the protein profiles of fresh tumors, their secreted proteins, as well as the patient's urine was carried out using state-of-the-art proteomic technology. We review the data concerning the putative marker psoriasin (S100A7), which, alone or in combination with other biomarkers, may be valuable for the noninvasive follow-up of patients bearing these tumors.