Rapidly progressive descending aortic pseudoaneurysm resulting from primary malignant fibrous histiocytoma.

A 66-year-old man with a history of asymptomatic bilateral swelling of the axillary lymph nodes was admitted with hoarseness and pain of the right knee. Computed tomography showed a large pseudoaneurysm deriving from descending aorta. We planned to resect the pseudoaneurysm, and repair the aortic wall. Resection of the pseudoaneurysm and patch-closure of the defect of the aorta were performed successfully. Pathological examination of the pseudoaneurysm revealed malignant fibrous histiocytoma. The clinical course was very miserable. Intrathoracic recurrence occurred 7 months after surgery, and he died of multiple brain metastases 10 months postoperatively.