title: Population-based outcomes of boost versus salvage radiosurgery for brain metastases after whole brain radiotherapy.
abstract: OBJECTIVE
  We conducted a retrospective population-based study to examine the survival outcomes in patients with brain metastases treated with salvage stereotactic radiosurgery (SRS), compared to boost SRS, after previous whole brain radiotherapy (WBRT).
  
  
  METHODS
  From January 2000 to June 2011, 191 patients treated with WBRT and SRS for brain metastases in British Columbia were studied. Patients were divided into a boost cohort and a salvage cohort. The criteria used to determine eligibility for SRS were: 1-3 metastases, ≤4cm size, Karnofsky performance status ≥ 70, and control of extracranial disease.
  
  
  RESULTS
  Diagnosis by primary site was 84 lung, 47 breast, 15 melanoma, 12 renal, 9 colorectal, and 24 other. There were 113 patients (59%) in the boost cohort and 78 patients (41%) in the salvage cohort. The median overall survival from WBRT for the whole population was 17.7months: 12.1 months for the boost cohort and 22.7 months for the salvage cohort. There was no difference in median survival after SRS for the boost and salvage cohorts (11.2 vs. 11.2 months, p=0.78).
  
  
  CONCLUSIONS
  In selected patients with brain metastases treated with WBRT, survival following salvage SRS is as good as survival after WBRT + boost SRS.
authors.affiliation: Abbotsford Centre, BC Cancer Agency, British Columbia, Canada. fhsu@bccancer.bc.ca
authors.forename: Fred
authors.initials: F
authors.lastname: Hsu
authors.forename: Para
authors.initials: P
authors.lastname: Kouhestani
authors.forename: Sonia
authors.initials: S
authors.lastname: Nguyen
authors.forename: Arthur
authors.initials: A
authors.lastname: Cheung
authors.forename: Michael
authors.initials: M
authors.lastname: McKenzie
authors.forename: Roy
authors.initials: R
authors.lastname: Ma
authors.forename: Brian
authors.initials: B
authors.lastname: Toyota
authors.forename: Alan
authors.initials: A
authors.lastname: Nichol
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001932:Brain Neoplasms / Q000401:mortality / Q000532:radiotherapy / Q000556:secondary* / Q000601:surgery*; D016371:Cranial Irradiation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016634:Radiosurgery; D012189:Retrospective Studies; D016879:Salvage Therapy; D016896:Treatment Outcome
keywords: Boost; Brain metastases; Population outcomes; Salvage; Stereotactic radiosurgery