title: Endoscopic biopsy of brain tumors in children: diagnostic success and utility in guiding treatment strategies.
abstract: OBJECTIVE
  Endoscopic biopsy is an important minimally invasive method of diagnosis in the initial management of lesions in children with intraventricular and periventricular tumors. The procedure can be performed in conjunction with CSF-diverting procedures for obstructive hydrocephalus. The authors present their single-institution experience in a predominantly pediatric series with respect to diagnostic efficacy, utility in guiding treatment plans, and safety.
  
  
  METHODS
  A retrospective review was conducted in a consecutive series of patients who underwent endoscopic biopsy of brain tumors during a 13-year period.
  
  
  RESULTS
  There were 33 endoscopic biopsies in 31 patients (16 males and 15 females). The average age of the patients was 11.3 years, with a mean follow-up duration of 2.4 years. The majority of biopsies were performed in conjunction with CSF-diverting procedures, such as endoscopic third ventriculostomy or fenestration of the septum pellucidum. Overall, 23 (70%) of 33 biopsies were diagnostic, with results that directed subsequent treatment. When stratified by tumor location, biopsy samples obtained in the lateral ventricle or pineal region were more favorable toward a successful diagnosis than those in the thalamus or tectal region. In 4 cases, elevated CSF tumor marker levels led to modification of the diagnosis and appropriate adjustment of treatment. The endoscopic third ventriculostomy success rate was 82.4%. There were 2 major complications (6.1%), which resulted in neurological deficits. There were no procedure-related deaths.
  
  
  CONCLUSIONS
  Endoscopic biopsy is an effective means of diagnosis of brain tumors in children. The diagnostic power may be more favorable with tumors in the lateral ventricle or pineal region. Collection of CSF during the procedure for tumor marker analysis is an integral component of diagnosis.
authors.affiliation: Division of Pediatric Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA. eahn4@jhmi.edu
authors.forename: Edward S
authors.initials: ES
authors.lastname: Ahn
authors.forename: Liliana
authors.initials: L
authors.lastname: Goumnerova
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001706:Biopsy; D001932:Brain Neoplasms / Q000150:complications / Q000473:pathology* / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004724:Endoscopy; D005260:Female; D006801:Humans; D006849:Hydrocephalus / Q000175:diagnosis / Q000209:etiology / Q000628:therapy; D007223:Infant; D008297:Male; D019635:Neurosurgical Procedures; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult