title: The current role of Gamma Knife radiosurgery in the management of intracranial haemangiopericytoma.
abstract: BACKGROUND
  Haemangiopericytomas (HPCs) are rare tumours characterised by aggressive behaviour with tendency to local recurrence and to metastasise. WHO grade II and grade III tumours show different progression-free survival and overall survival rates. Gross total tumour resection is still considered the treatment of choice. Adjuvant radiation therapies represent an option in the treatment strategy regardless the extent of resection. Based on this consideration, Gamma Knife radiosurgery has been introduced either as a primary treatment or as an adjuvant treatment for residual or recurrent tumours.
  
  
  METHODS
  A systematic search was performed on PubMed, Web of Science and Google Scholar for clinical series reporting Gamma Knife radiosurgery, Cyberknife and Linear Accelerator (LINAC) for the management of intracranial HPCs.
  
  
  RESULTS
  Fourteen studies focusing on the effects of Gamma Knife radiosurgery for intracranial HPCs were included. Four studies reported data on Cyberknife radiosurgery and LINAC. A total of 208 patients harbouring 366 tumours have been reported. Patient's features, radiosurgical treatment characteristics and follow-up data of the pertinent literature have been critically revised.
  
  
  CONCLUSIONS
  Gamma Knife radiosurgery and the other radiosurgical techniques represent a feasible and effective therapy in the management of HPCs. Tumour control and survival rate are comparable to those reported for radiotherapy. Further studies should be focused to define the exact role of Gamma Knife radiosurgery in the management of HPCs.
authors.affiliation: Department of Neurosurgery and Gamma Knife Radiosurgery, San Raffaele Scientific Institute, Vita-Salute University, Via Olgettina 60, 20132, Milano, Italy. spina.alfio@hsr.it.
authors.forename: Alfio
authors.initials: A
authors.lastname: Spina
authors.affiliation: Department of Neurosurgery and Gamma Knife Radiosurgery, San Raffaele Scientific Institute, Vita-Salute University, Via Olgettina 60, 20132, Milano, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Boari
authors.affiliation: Department of Neurosurgery and Gamma Knife Radiosurgery, San Raffaele Scientific Institute, Vita-Salute University, Via Olgettina 60, 20132, Milano, Italy.
authors.forename: Filippo
authors.initials: F
authors.lastname: Gagliardi
authors.affiliation: Department of Neurosurgery and Gamma Knife Radiosurgery, San Raffaele Scientific Institute, Vita-Salute University, Via Olgettina 60, 20132, Milano, Italy.
authors.forename: Carmine A
authors.initials: CA
authors.lastname: Donofrio
authors.affiliation: Department of Neurosurgery and Gamma Knife Radiosurgery, San Raffaele Scientific Institute, Vita-Salute University, Via Olgettina 60, 20132, Milano, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Franzin
authors.affiliation: Department of Neurosurgery and Gamma Knife Radiosurgery, San Raffaele Scientific Institute, Vita-Salute University, Via Olgettina 60, 20132, Milano, Italy.
authors.forename: Pietro
authors.initials: P
authors.lastname: Mortini
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000532:radiotherapy*; D005260:Female; D006393:Hemangiopericytoma / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016634:Radiosurgery / Q000009:adverse effects* / Q000379:methods; D016019:Survival Analysis
keywords: Brain tumour; Gamma Knife, radiosurgery; Haemangiopericytoma; Radiation therapy; Surgery