Primary metastatic (stage IV) Ewing tumor: Survival analysis of 171 patients from the EICESS studies

Background. In the multicenter European Intergroup Cooperative Ewing's Sarcoma Studies, localized Ewing tumors of bone were treated by combination chemotherapy with surgery and/or radiotherapy. Patients with primary metastases (pm-pts) were treated in high risk protocols. Patients and methods.. One hundred seventy-seven pm-pts were registered from January 1990 to December 1995, 171 were evaluable for survival analyses. Thirty-six pm-pts received myeloablative megatherapy with stem cell rescue following conventional treatment. Bilateral whole lung irradiation (WLI) was administered in 57 pm-pts with pulmonary involvement. Event-free survival (EFS) rates were estimated by Kaplan-Meier analysis. Prognostic factors were identified by log-rank statistics, Cox procedures and logistic regression. Results. Eighty-nine deaths were recorded by 1 February 1997, EFS four years after diagnosis for all 171 pm-pts was 0.27. EFS for isolated lung metastases was 0,34, for bone/bone marrow (BM) metastases, 0,28, and for combined lung plus bone/BM metastases, 0.14 (P < 0.005). WLI improved outcome in case of isolated pulmonary involvement (0.40 vs. 0.19, P < 0,05). In pm-pts with combined pulmonary/skeletal metastases, intensification by megatherapy and/or WLI improved EFS from 0.00 to 0.27 (P = 0.0001). Conclusions. EFS four years after diagnosis in patients with disseminated Ewing tumors is 0,27. Whole lung irradiation and megatherapy improve outcome in subgroups of patients with disseminated Ewing disease.