Analysis of prognostic factors in extraosseous Ewing sarcoma family of tumors: Review of St. Jude Children's Research Hospital experience

Background. Advances in the treatment of Ewing sarcoma family of tumors (ESFT) are the result of improvements in systemic and local therapies. Clinical data of extraosseous ESFT are scarce. Methods. A retrospective analysis of all patients with extraosseous ESFT treated at St. Jude Children's Research Hospital (SJCRH) from June 1982 to August 2009. Results. Forty-six patients with extraosseous ESFT were identified. The mean age at diagnosis was 13.8 years. The majority of patients were male and white. The most common site of primary tumor was the trunk. Twelve patients had subcutaneous tumors. The median tumor size was 8 cm. Six patients (13 %) had metastatic disease at diagnosis. A total of 59 % of patients were alive at the time of analysis, with a median follow-up from diagnosis of 15.3 years. Fifteen-year estimates of survival and eventfree survival (EFS) for all patients were 53.3 ± 9.4 and 50 ± 9.1 %, respectively. Fifteen-year estimates of survival and EFS with localized disease were 61.4 ± 9.8 and 57.6 ± 9.7 %, respectively. Stage and subcutaneous ESFT were significant predictors of outcome. There was no significant difference in patient's demographics and tumor characteristics between patients with skeletal ESFT and extraosseous Ewing sarcoma. The outcome for patients with localized extraosseous Ewing sarcoma was similar to that reported for all localized ESFT patients treated at SJCRH. Conclusions. The outcome for localized patients treated with extraosseous ESFT was similar to that reported for all ESFT patients treated on protocols at SJCRH. Patients with subcutaneous ESFT had a favorable prognosis when compared to their counterparts.