Role of Radiotherapy in the Multimodal Treatment of Ewing Sarcoma Family Tumors

Abstract

PURPOSE: The aim of this study was to evaluate the role of radiotherapy (RT) in the management of Ewing sarcoma family tumors (ESFT).

MATERIALS AND METHODS: Retrospective analysiswas performed on 91 patientswith localized ESFT treated from 1988 to 2012. Primary tumor size was ≥ 8 cm in 33 patients. Surgery, RT, and combined surgery with RT were applied in 37, 15, and 33 patients, respectively.

RESULTS: Median follow-up was 43.8 months. Forty-three patients (47.3%) showed recurrence or progressive disease. Twelve patients (13.2%) showed local failure after initial treatment. Thirty-nine patients (42.9%) experienced distant metastases. The 5-year overall survival (OS), progression-free survival, and local control (LC) were 60.5%, 58.2%, and 85.1%, respectively. According to treatment, 5-year LCwas 64.8% with RT and 90.2% with combined surgery and RT (p=0.052). Prognostic factors for OS were tumor size (≥ 8 cm, p < 0.001) and surgical resection (p < 0.001). In large tumors (≥ 8 cm), combined surgery and RT produced better LC compared to RT (p=0.033). However, in smaller tumors (< 8 cm), RT without surgery resulted in a similar LC rate as RT with surgery (p=0.374).

CONCLUSION: RT used for patients with unfavorable risk factors resulted in worse outcome than for patientswho received surgery. Smallertumors could be controlled locallywith chemotherapy and RT. For large tumors, combined surgery and RT is needed. Proper selection of local treatment modality, RT, surgery, or both is crucial in the management of ESFT.