title: Letter: Osteosarcoma--new hope.
mesh_terms: D001859:Bone Neoplasms / Q000188:drug therapy*; D002648:Child; D006801:Humans; D002955:Leucovorin / Q000627:therapeutic use; D008727:Methotrexate / Q000627:therapeutic use; D009362:Neoplasm Metastasis; D012516:Osteosarcoma / Q000188:drug therapy*
chemical_list: D002955:Leucovorin; D008727:Methotrexate