Mediastinal liposarcoma masquerading as penetrating aortic ulcer in the descending aorta: a case report.

A 56-year-old woman with a history of hypertension and cerebral infarction was admitted to the hospital complaining of progressive and severe chest pain for 1 day. CT scan revealed a descending penetrating ulcer. Accordingly, she underwent an uneventful endovascular repair with a thoracic endograft. One month later the patient presented to our clinic with chest and back pain again. The contrast CT indicated that the periaortic mass grew larger, which interpreted as hematoma resulting from endoleak. But no endoleak was found by angiography. CT-guided needle biopsy was carried out, the histology of the mass revealed a pleomorphic liposarcoma. Liposarcomas are malignant fat-containing tumors derived from mesenchymal cells that typically occur in the extremities and retroperitoneum, mediastinal liposarcoma account for less than 1% in mediastinal malignancies; pleomorphic liposarcoma is the least common liposarcomas. Cases of liposarcoma invading vascular system are seldom, to our knowledge, it is the first case of mediastinal pleomorphic liposarcoma invaded the descending aorta. It is worth mentioning that in the modern endovascular era, the majority of aortic diseases are being repaired by endovascular techniques. When patients with growing periaortic mass post endovascular repair and endograft-related causes have been excluded, the rare possibility of mediastinal liposarcoma should arise as a differential diagnosis. Promptly CT-guided biopsy help establish an early diagnosis.