title: Efficacy of stereotactic radiotherapy as salvage treatment for recurrent malignant gliomas.
abstract: OBJECTIVE
  To evaluate the efficacy and toxicity of CyberKnife stereotactic radiotherapy (SRT) for recurrent glial tumors previously treated with high-dose radiotherapy.
  
  
  METHODS
  CyberKnife SRT was performed in 37 patients with recurrent glial tumors who presented to our hospital between January 2007 and March 2012. The patients were subjected to a dose ranging from 20 to 28 Gy using the CyberKnife system with an average of two fractions. The median follow-up duration after SRT was 14 months (range 1.8-57).
  
  
  RESULTS
  The median survival time of the patients after recurrence was 22.3 months (95% confidence interval/95% Cl 12.5-32). The median survival times of the high- and low-grade patients were 29 and 19 months, respectively. No significant toxicity due to radiation was noticed during the follow-up period. No factor influencing mortality was found in either the univariate or multivariate analysis.
  
  
  CONCLUSIONS
  SRT using CyberKnife is an effective and safe treatment choice for recurrent glial tumors. SRT achieves a more favorable outcome in the treatment of recurrent tumors, particularly in high-grade ones.
authors.affiliation: Inonu University School of Medicine, Turgut Ozal Medical Center, Radiation Oncology, Malatya, Turkey.
authors.forename: Kemal
authors.initials: K
authors.lastname: Ekici
authors.forename: Naciye
authors.initials: N
authors.lastname: Ozseker
authors.forename: Alpaslan
authors.initials: A
authors.lastname: Mayadagli
authors.forename: Mihriban
authors.initials: M
authors.lastname: Erdogan Kocak
authors.forename: Ali
authors.initials: A
authors.lastname: Olmezoglu
mesh_terms: D001932:Brain Neoplasms / Q000532:radiotherapy*; D005910:Glioma / Q000532:radiotherapy*; D006801:Humans; D009364:Neoplasm Recurrence, Local; D016634:Radiosurgery; D016879:Salvage Therapy