title: Stereotactic radiosurgery in the management of brain metastases: an institutional retrospective analysis of survival.
abstract: OBJECTIVE
  The objective of this study was to report our experience with stereotactic radiosurgery performed with the Gamma Knife (GK) in the treatment of patients with brain metastases and to compare survival for those treated with radiosurgery alone with survival for those treated with radiosurgery and whole-brain radiotherapy.
  
  
  METHODS
  Prospectively collected demographic and clinical characteristics and treatment and survival data on 237 patients with intracranial metastases who underwent radiosurgery with the GK between 2003 and 2007 were reviewed. Kaplan-Meier and Cox proportional hazards regression analyses were used to compare survival by demographic and clinical characteristics and treatment.
  
  
  RESULTS
  The mean age of the patient population was 56 years. The most common tumor histologies were non-small-cell lung carcinoma (34.2%) and breast cancer (13.9%). The median overall survival time was 8.5 months from the time of treatment. The median survival times for patients with one, two/three, and four or more brain metastases were 8.5, 9.4, and 6.7 months, respectively. Patients aged 65 years or greater and those aged less than 65 years had median survival times of 7.8 and 9 months, respectively (p = 0.008). The Karnofsky Performance Score (KPS) at the time of treatment was a significant predictor of survival: those patients with a KPS of 70 or less had a median survival of 2.9 months compared with 10.3 months (p = 0.034) for those with a KPS of 80 or greater. There was no statistically significant difference in survival between patients treated with radiosurgery alone and those treated with radiosurgery plus whole-brain radiotherapy.
  
  
  CONCLUSIONS
  Radiosurgery with the GK is an efficacious treatment modality for brain metastases. A KPS greater than 70, histology of breast cancer, smaller tumor volume, and age less than 65 years were associated with a longer median survival in our study.
authors.affiliation: Department of Neurosurgery, The Johns Hopkins University School of Medicine and Bloomberg School of Public Health, Baltimore, MD, USA.
authors.forename: James L
authors.initials: JL
authors.lastname: Frazier
authors.forename: Sachin
authors.initials: S
authors.lastname: Batra
authors.forename: Sumit
authors.initials: S
authors.lastname: Kapor
authors.forename: Ananth
authors.initials: A
authors.lastname: Vellimana
authors.forename: Rahul
authors.initials: R
authors.lastname: Gandhi
authors.forename: Kathryn A
authors.initials: KA
authors.lastname: Carson
authors.forename: Ori
authors.initials: O
authors.lastname: Shokek
authors.forename: Michael
authors.initials: M
authors.lastname: Lim
authors.forename: Lawrence
authors.initials: L
authors.lastname: Kleinberg
authors.forename: Daniele
authors.initials: D
authors.lastname: Rigamonti
mesh_terms: D000368:Aged; D001932:Brain Neoplasms / Q000401:mortality* / Q000556:secondary / Q000601:surgery*; D001943:Breast Neoplasms / Q000473:pathology; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality* / Q000556:secondary / Q000601:surgery*; D005260:Female; D006801:Humans; D017567:Karnofsky Performance Status; D008175:Lung Neoplasms / Q000473:pathology; D008297:Male; D008875:Middle Aged; D016634:Radiosurgery / Q000295:instrumentation / Q000379:methods / Q000401:mortality; D012044:Regression Analysis; D012189:Retrospective Studies; D016019:Survival Analysis