Periosteal Ewing's sarcoma.

Ewing's sarcoma is a small cell malignant tumor that usually arises in the medullary cavity of bone. Less frequently, it originates in soft tissue and may secondarily invade underlying bone. The origin of Ewing's sarcoma in a periosteal location without extension into either the bone or adjacent soft tissue has not been clearly documented. Other malignant tumors of bone (e.g., osteosarcoma) appear to have a somewhat better prognosis when confined between periosteum and bone. The case of a patient with a periosteal Ewing's sarcoma who received a radical excision and postoperative chemotherapy and who is without evidence of disease with over 2 years follow-up is reported.