Giant retrovesical epithelioid hemangioendothelioma presenting with acute urinary retention: a case report.

Epithelioid hemangioendothelioma (EH) is a very rare vascular tumor of intermediate biological behavior. It can arise from various sites including bone, liver, spleen, pleura, lung, skin, or soft tissue. We report a case of a 24-year-old man who presented with a history of acute urinary retention and a palpable lump in the lower abdomen. Imaging showed a large pelvic mass displaying heterogeneous texture with solid and cystic components compressing and displacing adjacent structures. The patient underwent exploratory laparotomy with excision of the pelvic mass. Histopathological examination confirmed the diagnosis of EH. Pelvic soft tissue origin of EH is extremely rare. The diagnosis of EH may be suggested by characteristic magnetic resonance imaging (MRI) findings.