Prognostic factors and survival in patients under 18 years of age with Ewing sarcoma family tumors: a 10-year experience

Abstract

Objective: To describe the clinical and epidemiological characteristics, and to determine prognostic factors, event-free survival (EFS) and overall survival (OS) of patients with Ewing sarcoma family tumors (ESFT). Materials and methods: A retrospective study conducted in patients under 18 years of age with ESFT, treated at the Unit of Pediatric and Adolescent Oncology of the Hospital Edgardo Rebagliati between January 2006 and June 2016. The descriptive analysis was performed by frequency distribution. Kaplan-Meier curves were used for EFS and OS analysis. Univariate and multivariate analyses were performed according to the Cox regression model for demographic, clinical and surgical variables, and prognostic factors. The measure of strength of association was expressed in hazard ratio (HR) and 95% confidence interval (95% CI), and p<0.05 was considered for significant differences. Results: There were 29 cases of ESFT. The median age was 9 years (range 2-17), 55% were males. The most frequent location was the pelvis (31%). Fifty-nine percent (59%) had metastasis at diagnosis. The 3-year EFS in localized ESTF was 40.4% (± 14.4 EE) and with metastasis was 14.6% (± 12.2, EE). The 3-year OS in localized ESTF was 53.9% (± 17.8 EE) and with metastatic disease was 15.1% (± 9.7, EE). The tumor size ≥5cm (HR 14.84, p=0.01) and the presence of metastasis at the onset of the disease (HR 3.23, p=0.01) were independent prognostic factors of worse OS. There was no significant difference in prognosis regarding the gender, age, histological type, involvement of surgical borders or location of the tumor. Conclusions: ESFT are highly aggressive. The prognostic factors that contribute to a lower EFS and OS are the presence of metastasis at the onset of the disease and a tumor size ≥5cm.

Keywords

• Ewing sarcoma
• neuroectodermal tumors
• primitive
• peripheral
• prognosis
• survivorship