Urothelial carcinoma of the bladder is a frequent disease that can be identified timely by screening patients at high risk. Due to the high rate of disease recurrence, frequent follow-up procedures are necessary. For this purpose, cystoscopy is the standard procedure, and supplementary non-invasive procedures such as cytology or tumor marker tests are used. These tests have different advantages and disadvantages in terms of their sensitivities and specificities. Thus, they provide additional information, but are not able to replace cystoscopy as the standard instrument in the diagnosis of bladder cancer.