title: Gamma knife radiosurgery for high grade glial neoplasms: a Canadian experience.
abstract: OBJECTIVE
  To review our institutional experience with Gamma Knife (GK) stereotactic radiosurgery in treating focally recurrent high grade glial neoplasms of World Health Organization (WHO) grade III or IV.
  
  
  METHODS
  We conducted a retrospective cohort review of all patients treated with GK for focally recurrent high grade gliomas at our institution between November 2003 and April 2013. Data on age, sex, tumor volume, location and maximal diameter, presenting clinical status, complications and clinical outcome was recorded.
  
  
  RESULTS
  A total of 33 patients were identified. Four were lost to follow-up. Average post-GK and overall survival was 20.4 months (range: 3–72) and 63.3 months (range: 10–214) respectively. For WHO grade IV gliomas, the average post-GK and overall survival was 15.8 months (range: 3–77) and 40.1 months (range: 13–148) respectively. Similarily, for WHO grade III gliomas, the average post-GK and overall survival was 34.9 months (range: 6–72) and 136.4 months (range: 22–214) respectively. Twenty-two patients (75.9%) had post-GK edema, with 14 requiring dexamethasone and eight being asymptomatic. Four patients (13.8%) had imaging defined radiation necrosis.
  
  
  CONCLUSIONS
  Gamma Knife SRS affords an extension of local tumor control, acceptable morbidity, and potentially prolonged survival, for highly selected patients with focally recurrent high grade glial neoplasms.
  
  
  
  Radiochirurgie par scalpel gamma pour les néoplasies gliales de haut grade de malignité : une expérience canadienne.
authors.forename: F A
authors.initials: FA
authors.lastname: Zeiler
authors.forename: A M
authors.initials: AM
authors.lastname: Kaufmann
authors.forename: P J
authors.initials: PJ
authors.lastname: McDonald
authors.forename: D
authors.initials: D
authors.lastname: Fewer
authors.forename: J
authors.initials: J
authors.lastname: Butler
authors.forename: G
authors.initials: G
authors.lastname: Schroeder
authors.forename: M
authors.initials: M
authors.lastname: West
mesh_terms: D002170:Canada; D005910:Glioma / Q000601:surgery; D006801:Humans; D009364:Neoplasm Recurrence, Local; D016634:Radiosurgery; D012189:Retrospective Studies