*High Risk R2: in a randomised trial, to examine whether high-dose chemotherapy using busulfan-melphalan with autologous stem cell reinfusion, compared with standard chemotherapy, improves event-free survival in patients with localised Ewing sarcoma and poor histological response or tumour volume ≥200 mL (R2loc). In patients with pulmonary metastases high dose busulfan-melphalan chemotherapy with autologous stem cell reinfusion is randomised versus standard chemotherapy plus whole lung irradiation (R2pulm).