Pseudoangiosarcomatous Urothelial Bladder Carcinoma A Report of Two New Cases with Clinicopathological and Immunohistochemical Findings: Importance of Recognizing This Rare Morphological Pattern

BACKGROUND: Although pseudoangiosarcomatous carcinoma is a relatively common morphological carcinoma subtype, mainly of skin squamous carcinomas, it is less frequently found in mucosas and other organs and is very rare in the urinary tract, e.g., urinary bladder, with just a handful of cases reported in the largest series. CASES: We would like to report 2 pseudosarcomatous urothelial bladder carcinomas with clinicopathological correlation and immunohistochemical findings and with an analysis of intercellular adhesion protein expression (E-cadherin and syndecan-1) (in these cases they appeared either diminished or absent). CONCLUSION: This specific growth pattern, closely resembling vasoformative neoplasias, is associated with large, discohesive, lytic tumors with abundant necrosis. It correlates with high stage at diagnosis, has a dismal prognosis, and is recognizable even by transurethral biopsy (TURB).