Chordoma periphericum: a case report.

The authors describe a tumor that had the histologic and ultrastructural features and immunohistochemical profile of an axial chordoma, but arose in the distal ulna. A skeletal survey failed to show any other site of involvement. The tumor was resected, and the patient remains free of disease 2 1/2 years later. Rare tumors with the histologic features of chordoma have been reported in appendicular locations. Chordoma periphericum, a tumor that has the potential to metastasize, needs to be distinguished from parachordoma because no classic parachordoma has been reported to disseminate.