Extraskeletal Ewing's sarcoma: results of combined modality treatment.

Eleven patients with extraskeletal Ewing's sarcoma (EES) were treated with combined modality therapy at the National Cancer Institute. The diagnosis of EES was reserved for lesions that were identical to Ewing's sarcoma of bone by light and electron microscopy. Diagnostic work-up to rule out a skeletal primary included bone scan, localized views of adjacent bone, and bone tomography. Seven patients presented with an extremity primary and four patients had a truncal primary. No patients had evidence of metastases at presentation. Patients were treated with combined modality therapy consisting of high-dose local irradiation and vincristine, actinomycin D, and cyclophosphamide chemotherapy following a biopsy or local excision. No attempt was made to excise widely the primary tumor mass. Gross tumors generally responded rapidly to the combined modality treatment. Of 11 patients, seven (64%) remain disease free, with a follow-up of three to seven years from completion of therapy. Long-term local control was established in nine of 11 patients (82%). Autopsy findings on two patients with local failure showed no tumor involvement of adjacent bone. Attempts at gross resections by radical surgical procedures do not routinely appear to be necessary in light of the high local control rates with high-dose irradiation.