Pelvic Lymphangioma: The Purpose of a Clinical Case.

Lymphangioma is a benign vascular malformation characterized by abnormal proliferation of lymphatic vessels, resulting in the formation of lymphatic masses or cysts. Pelvic lymphangiomas may remain asymptomatic for long periods and are often discovered incidentally during imaging studies performed for other reasons. When symptomatic, they may cause manifestations related to compression of adjacent structures, such as abdominal pain and distension, urinary retention, or gastrointestinal symptoms. We report the clinical case of a 37-year-old male patient with no relevant medical history who presented to the emergency department twice within two months due to urinary retention. As part of the etiological study, a computed tomography (CT) scan revealed a large, lobulated pelvic mass of uncertain characterization, raising suspicion for a necrotic mass, fluid collection, lymphangioma, or another cause. Subsequently, pelvic magnetic resonance imaging (MRI) supported the diagnostic hypothesis of lymphangioma. The patient was referred to the Portuguese Institute of Oncology (IPO), Lisbon, where he underwent elective surgery. Histopathological examination confirmed the diagnosis of pelvic lymphangioma.