Department of Pathology, Laboratore Spec, Diagnostiky, Medical Faculty Hospital, Alej Svobody 80, 323 18 Pilsen, Czech Republic. HES@fnplzen.cz.
ABSTRACT: We present the case of 80-year-old male with superficial papillary urothelial carcinoma of the urinary bladder with striking multicystic architecture with a combination of features of urothelial carcinoma with gland-like lumina, with signet-ring cell differentiation and microcystic pattern. However, the tumor shared the morphologic features of several variants of urothelial carcinoma, the most important differential diagnosis covered so-called florid Brunneriosis, cystitis cystica, and primary adenocarcinomas of the urinary bladder.