LATE DEVELOPMENT OF A MALIGNANT FIBROUS HISTIOCYTOMA AT THE SITE OF AGIANT-CELL TUMOR

A case of late development of a high grade malignant fibrous histiocyt oma at the site of a previously surgically treated giant cell tumor is reported, The patient initially was treated for a benign giant cell t umor of the lateral condyle of the distal femur by curettage, implant of auto- and allograft bone, but no radiation. Eighteen years later, h e noted progressively increasing pain and disability, Radiographs show ed some change, but magnetic resonance imaging clearly disclosed a tum or arising at the site and extending outside the bone, After chemother apy, the tumor was resected and histologically showed no evidence of a recurrent giant cell tumor, only a high grade malignant fibrous histi ocytoma.