[Necrotic lipoma of the posterior mediastinum].

Lipomas are well-differentiated, encapsulated masses composed of adipocytes. Intrathoracic lipomas are rare, but found most commonly in the pleura or anterior mediastinum. Computed tomography shows fatty, homogenous content of the mass and will establish the diagnosis. Areas with a higher fat density are suggestive of liposarcoma. We describe a case of lipoma in the posterior mediastinum that contained solid areas on computed tomography. Histology showed that these areas were fat necrosis.