The Role of Radiation Therapy in Localized Ewing' Sarcoma

Ewing's sarcoma is a radiosensitive tumor that has historically been treated primarily with radiation therapy (RT). With the introduction of effective systemic therapy in the early 1970s, RT remained the primary local control modality until recently. With the concern about second tumors in the irradiated field and improved surgical techniques, surgical resection is currently playing a more important role in the management of these tumors. There have been no randomized trials comparing radiation with surgery, and in most series, patients with smaller tumors in accessible sites are treated with surgical resection. Retrospective reviews typically show a greater advantage to the use of surgery than do prospective trials. Although there may be slight local control advantage to surgery, the survival advantage is not great. Since the mid-1980s, fields tailored to the tumor volume have been recommended and the use of whole-bone irradiation has been abandoned. Local control has not been adversely effected. The intergroup trials for Ewing's sarcoma have recommended 45 Gy to a larger volume followed by a 10 Gy boost since 1978. Data from other studies suggest that the dose may be decreased in selected situations. Older studies of functional outcome report significant late effects related to radiation, but these seem to be reduced in more recent series.