The importance of recognizing malignant giant cell tumor of soft parts.

Four tumors in the extremities were initially diagnosed as extraskeletal osteogenic sarcoma. Recent review of these tumors had led to their reclassification. Three of these are now recognized as malignant giant cell tumors of soft tissue and one as a malignant fibrous histiocytoma. All four patients have been cured. Some special features of malignant giant cell tumors of soft parts are described. The importance of treatment planning is stressed.