Dedifferentiated Liposarcoma of the Retroperitoneum: A case report

ABSTRACT

We report a case of dedifferentiated liposarcoma of retroperitoneum as a recurrent form in a 41 year old male. The patient received a extirpation for retroperitoneal mass and diagnosed as myxoid liosarcoma 4 years ago. The patient experienced 3 recurrences over a period of 4 years and diagnosed as myxoid liposarcoma in the second, third recurrence also. Histologically, the mass was composed of several clearly distinct elements well differentiated liposarcoma, myxoid liposarcoma, myxoid malignant fibrous histiocytoma, poorly differntiated sarcoma, and fibrosarcoma. Immunohistochemically, S-100 protein was expressed in the area of spindle cell sarcoma, well differentiated liposarcoma, and malignant fibrous histiocytoma but alpha-1-antichymotrypsin was only expressed in the area of myxoid malignant fibrous histiocytoma.