Retroperitoneal lipomas: A case report.

Lipomas are mesenchymal tumors characterized by the abnormal proliferation of adipocytes. We describe a case of retroperitoneal lipomas in a patient with chronic lymphatic leukemia, who was referred to our sonography unit for a regular (6-month) follow-up scan. She had no abdominal symptoms of note. The sonographic examination revealed two well-defined, hyperechoic, oval-shaped masses: the first situated between the posterior wall of the stomach, the duodenum, and the head of the pancreas; the second lying craniomedial to the left kidney. Neither of the masses exhibited intralesional vascularization on color Doppler imaging. Retrospective examination of previous CT scans revealed that the lesions had been present for the past 4 years. Their slow growth was consistent with the suspicion of retroperitoneal lipomas, and this diagnosis was confirmed by magnetic resonance imaging. CT and MRI are the imaging studies of choice for diagnosing retroperitoneal lipomas, but ultrasonography is ideal for the follow-up of these patients because it is repeatable and relatively low in cost.