title: Gamma Knife surgery for brainstem metastases.
abstract: OBJECTIVE
  The goal of this study was to assess neuroimaging and clinical outcomes in patients harboring brainstem metastases that were treated with the Leksell Gamma Knife.
  
  
  METHODS
  Twenty-eight patients with brainstem metastases (32 lesions: 8 midbrain, 21 pontine, and 3 medullary) were consecutively treated with GKS. The primary cancer diagnoses in this group included 22 cases of lung cancer, 5 cases of breast cancer, and 1 case of rectal cancer. The median age of the patients was 61 years (range 45-83 years). The median treated lesion volume was 0.78 cm(3) (range 0.03-5.6 cm(3)), and the median GKS margin dose was 16 Gy (range 12-20 Gy). Overall survival in these patients was calculated using the Kaplan-Meier method.
  
  
  RESULTS
  The median survival time was 9 months after GKS (range 2-32 months). Survival was 39.3% at 1 year and 10.7% at 2 years. The tumor control rate in the series was 90.6% (29 of 32 lesions). Development of peritumoral edema occurred in 1 patient after GKS; 4 months after GKS, the edema disappeared.
  
  
  CONCLUSIONS
  Gamma Knife surgery using a median margin dose of 16 Gy is a safe and effective local therapy for patients with brainstem metastases.
authors.affiliation: Department of Neurosurgery and Gamma Knife Center, Tianjin Medical University 2nd Hospital, Tianjin, People's Republic of China.
authors.forename: Yanhe
authors.initials: Y
authors.lastname: Li
authors.forename: Desheng
authors.initials: D
authors.lastname: Xu
authors.forename: Zhiyuan
authors.initials: Z
authors.lastname: Zhang
authors.forename: Yipei
authors.initials: Y
authors.lastname: Zhang
authors.forename: Dong
authors.initials: D
authors.lastname: Liu
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Liu
authors.forename: Guokai
authors.initials: G
authors.lastname: Wang
authors.forename: Yiguang
authors.initials: Y
authors.lastname: Lin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001933:Brain Stem / Q000473:pathology / Q000601:surgery*; D020295:Brain Stem Neoplasms / Q000401:mortality / Q000556:secondary / Q000601:surgery*; D001943:Breast Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016634:Radiosurgery / Q000295:instrumentation* / Q000401:mortality; D015996:Survival Rate; D016896:Treatment Outcome