[Complicated sigmoid neoplasia with vesico-sigmoid fistula].

Being confronting with two apparently similar cases of entero-vesical fistulas, but complete different concerning the etiopathogeny, surgical management and prognosis, we believe that both communities--urologists and general surgeons--must know how to manage such cases. The tumors involving two or many systems or organs make the surgeon's decision be extremely difficult if not familiarized with both pathologies. We expose these unusual cases in order to demonstrate these affirmations.