IfosfamideMesnaAntineoplastic Agents, AlkylatingEtoposideAntineoplastic Combined Chemotherapy ProtocolsSarcomaCisplatinDrug Administration ScheduleSoft Tissue NeoplasmsDoxorubicinCarboplatinSalvage TherapyGerminomaInfusions, IntravenousSarcoma, EwingCombined Modality TherapyBone NeoplasmsTreatment OutcomeVincristineGranulocyte Colony-Stimulating Factor