The current classification of urothelial neoplasms.

The classification of urothelial neoplasms has been a subject of significant controversy and debate over the last decade. Only recently has a general level of agreement developed on the utility of the classification first proposed by the World Health Organization and the International Society of Urologic Pathology in 1998. Recent adoption of this scheme in therapeutic guidelines indicates the clinical utility of the system. In this review a brief historical perspective is presented, followed by a review of the classification system, the histological criteria for the specific categories and the clinical significance of these diagnoses.