title: Natural history and outcome of optic pathway gliomas in children.
abstract: BACKGROUND
  The optimal management of optic pathway gliomas (OPGs) is complicated by their variable natural history, the association with neurofibromatosis type 1 (NF1) and difficulties in defining progression and response to treatment.
  
  
  METHODS
  This study is a retrospective review of all children presenting to a single institution with an OPG between 1990 and 2004.
  
  
  RESULTS
  Of the 133 children included, 78 (59%) had NF1; 87 (71 NF1) were observed initially, of whom 23 (11 NF1) subsequently required treatment. Forty-six patients received immediate treatment. Initial treatment, without or with an observation period, comprised chemotherapy alone (32, 11 NF1); debulking + chemotherapy (15, 4 NF1); gross total resection (6); radiotherapy (2); debulking + radiotherapy (3); and debulking only (12, 3 NF1). Overall, 16 patients were irradiated during the study period. Four children died (overall survival at 5 and 10 years was 97.6% and 94.6% for those who required treatment). Progression-free survival (PFS) for the 69 patients who needed treatment was 48%. There was no difference in PFS between chemotherapy versus chemotherapy + debulking or debulking alone. PFS for the NF1 patients who required treatment was similar to that of non-NF1 patients. Mean follow-up time was 9.0 (range 0.6-18.0, median 8.6) years.
  
  
  CONCLUSIONS
  The study confirms the complexity of OPGs and that NF1 is a major determinant of the resultant behavior of the tumor.
authors.affiliation: Pediatric Brain Tumor Program, Division of Hematology/Oncology, Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Gary
authors.initials: G
authors.lastname: Nicolin
authors.forename: Patricia
authors.initials: P
authors.lastname: Parkin
authors.forename: Donald
authors.initials: D
authors.lastname: Mabbott
authors.forename: Darren
authors.initials: D
authors.lastname: Hargrave
authors.forename: Ute
authors.initials: U
authors.lastname: Bartels
authors.forename: Uri
authors.initials: U
authors.lastname: Tabori
authors.forename: James
authors.initials: J
authors.lastname: Rutka
authors.forename: J Raymond
authors.initials: JR
authors.lastname: Buncic
authors.forename: Eric
authors.initials: E
authors.lastname: Bouffet
mesh_terms: D000293:Adolescent; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use; D001925:Brain Damage, Chronic / Q000209:etiology; D016190:Carboplatin / Q000008:administration & dosage; D002648:Child; D002675:Child, Preschool; D003131:Combined Modality Therapy; D016371:Cranial Irradiation / Q000009:adverse effects; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008607:Intellectual Disability / Q000209:etiology; D008130:Lomustine / Q000008:administration & dosage; D008297:Male; D009456:Neurofibromatosis 1 / Q000453:epidemiology; D020339:Optic Nerve Glioma / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology* / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery; D011344:Procarbazine / Q000008:administration & dosage; D012189:Retrospective Studies; D016019:Survival Analysis; D013866:Thioguanine / Q000008:administration & dosage; D016896:Treatment Outcome; D014747:Vinblastine / Q000008:administration & dosage; D014750:Vincristine / Q000008:administration & dosage; D014786:Vision Disorders / Q000209:etiology
chemical_list: D011344:Procarbazine; D014750:Vincristine; D014747:Vinblastine; D008130:Lomustine; D016190:Carboplatin; D013866:Thioguanine