Effect of low-dose radiation therapy when combined with surgical resection for Ewing sarcoma

As an alternative to high-dose irradiation, limited surgery and low-dose irradiation have been investigated as a means to achieve local control. We retrospectively examined the clinical characteristics, treatment, and outcome for 25 patients with Ewing sarcoma treated with limited surgery and low-dose irradiation.

The records of 25 patients (age 4-48 years) were reviewed who were treated between 1979 and 1996 at Memorial Sloan-Kettering Cancer Center. At the time of diagnosis, 21 of the 25 patients had prognostically unfavorable tumors including the presence of metastatic disease (n = 12), an axial primary (n = 17), and a tumor measuring greater than 8 cm (n = 18). The primary tumor was completely resected (wide local excision) in 13 patients, incompletely resected (marginal excision) in 7 patients, and biopsied only in the remaining 5 patients. The median dose of irradiation to the primary site was 30 Gy.

With a median follow-up of 67 months (range 16-189 months) for the surviving patients, 28% failed distantly, and an additional 28% suffered from the progression of previously established metastatic disease. No patient failed locally. The median overall survival was 43 months. The actuarial overall survival at 5 years was 39% (+/-11%) for all patients and 60% (+/-14%) for patients with localized disease.

Limited surgery and postoperative irradiation are one strategy that promises to balance the goal of achieving local control with the goal of diminishing late effects. Apart from the scenario in which radiation therapy is absolutely unnecessary, low-dose irradiation may be appropriate after considering the risk for local recurrence and overall prognosis.