Pleomorphic lipoma in the middle mediastinum.

Mediastinal pleomorphic lipoma was found in a 63-year-old Thai male who presented with problems of chronic cough, dyspnea and dysphagia for 1 year. CT and MRI studies revealed a well-circumscribed mass in the middle mediastinum. Thoracotomy was performed and excision of the tumor was done completely. The pathological features of the tumor were typical of pleomorphic lipoma. While lipomas are common tumors in the mediastinum, liposarcomas are rare and there has been no reported case of mediastinal pleomorphic lipoma before. Differential diagnosis of liposarcoma was very important in this case due to different clinical courses and prognoses.