Intraoperative Electron-Beam Radiation Therapy for Pediatric Ewings Sarcomas and Rhabdomyosarcomas: Long-Term Outcomes
Menée sur 71 patients pédiatriques atteints d'un sarcome d'Ewing ou d'un rhabdomyosarcome traité entre 1983 et 2012 (durée médiane de suivi : 72 mois), cette étude évalue l'efficacité, du point de vue des taux de contrôle local, de survie sans maladie et de survie globale à 10 ans, et la tolérabilité d'une radiothérapie par faisceaux d'électrons
Purpose : To assess long-term outcomes and toxicity of intraoperative electron-beam radiation therapy (IOERT) in the management of pediatric patients with Ewing sarcomas (EWS) and rhabdomyosarcoma (RMS). Methods and Materials : Seventy-one sarcoma (EWS; n=37, 52%; RMS; n=34, 48%) patients underwent IOERT for primary (n=46, 65%) or locally recurrent sarcomas (n=25, 35%) from May 1983 to November 2012. Local control (LC), overall survival (OS) and disease-free survival (DFS) were estimated using Kaplan-Meier methods. For survival outcomes potential associations were assessed in univariate and multivariate analyses using the Cox proportional hazards model. Results : After a median follow-up of 72 months (range, 4-310 months), 10-year LC, DFS, and OS was 74%, 57%, and 68%, respectively. In multivariate analysis after adjustment for other covariates, disease status (p=0.04 and p=0.05) and R1 margin status (p<0.01 and p=0.04) remained significantly associated with LC and OS. Nine patients (13%) reported severe chronic toxicity events (all grade 3). Conclusions : A multimodal IOERT-containing approach is a well-tolerated component of treatment for pediatric EWS and RMS patients, allowing reduction or substitution of external beam irradiation exposure while mantining high local control rates.