[Carcinosarcoma of the urinary bladder. Report of three cases].

BACKGROUND: Carcinosarcoma of the urinary bladder is a very rare neoplasm accounting for less than 0,05% of urothelial tumours is a biphasic malignant neoplasm with only 79 cases reported in the English literature. Histologically, it exhibits morphologic and/or immunohistochemical evidence of epithelial and mesenchymal differentiation with the presence or absence of heterologous elements. It usually involves aged adults after 60 years and it has a poor prognosis. AIM: We report three cases with an emphasis on unusual histologic features. CASES: Three male patients age 76 to 86 years were found to have polypoid masses in the urinary bladder. In all cases, microscopic examination revealed biphasic neoplasms with distinct mesenchymal and epithelial components. The two first cases were remarkable respectively by the presence of chondrosarcomatous and osteosarcomatous components.