Fig. 2From: What is new in Genitourinary Pathology? Recent developments and highlights of the new 2016 World Health Organization classification of tumors of the urinary system and male genital organs a Urothelial dysplasia is a flat preneoplastic lesion demonstrating a degree of cytologic and architectural abnormalities that fall short of urothelial carcinoma in-situ. b Cytokeratin 20 exhibits diffuse full thickness reactivity in dysplastic urothelium (bottom), while in the normal urothelium only umbrella cells are positive (top)Back to article page