title: Frameless, real-time, surface imaging-guided radiosurgery:  clinical outcomes for brain metastases.
abstract: BACKGROUND
  Frameless stereotactic radiosurgery is commonly used to treat intracranial metastases, but mask-based immobilization can be uncomfortable for patients.
  
  
  OBJECTIVE
  To describe the clinical outcomes using a novel real-time, frameless, surface imaging--guided radiosurgery (SIG-RS) technique to treat brain metastases.
  
  
  METHODS
  Data were prospectively gathered for 44 consecutive patients totaling 115 intracranial metastases treated with SIG-RS in a median of 1 fraction (range, 1-5) to a median dose of 20 Gy (range, 15-30 Gy). Local control, regional control, and overall survival were estimated by the Kaplan-Meier method.
  
  
  RESULTS
  Median follow-up for all patients was 6.0 months (range, 0.3-21.6 months), with 31 of 44 (70%) deceased at the time of analysis. The 35 patients (80%) with follow-up imaging totaled 88 lesions evaluable for local control. Actuarial 6- and 12-month local control was 90% (95% confidence interval, 82-98) and 76% (95% confidence interval, 60-91), respectively. Regional failure was observed in 16 patients (46%). The median actuarial overall survival was 7.7 months (95% confidence interval, 5.7-9.7). Analysis of the subset of 22 patients (55 lesions) who received SIG-RS alone (no prior treatment) in a single fraction yielded comparable clinical outcomes. Grade 3 or greater toxicity occurred in 4 patients (9%). The median treatment time from beam on to beam off was 15 minutes (range, 3-36 minutes).
  
  
  CONCLUSIONS
  SIG-RS for treating intracranial metastases can produce clinical outcomes comparable to those with conventional frame-based and frameless stereotactic radiosurgery techniques while providing greater patient comfort with an open-faced mask and fast treatment times.
authors.affiliation: Department of Radiation Oncology, Center for Advanced Radiotherapy Technologies, University of California San Diego, La Jolla, California 92093-0843, USA.
authors.forename: Hubert
authors.initials: H
authors.lastname: Pan
authors.forename: Laura I
authors.initials: LI
authors.lastname: Cerviño
authors.forename: Todd
authors.initials: T
authors.lastname: Pawlicki
authors.forename: Steve B
authors.initials: SB
authors.lastname: Jiang
authors.forename: John
authors.initials: J
authors.lastname: Alksne
authors.forename: Nicole
authors.initials: N
authors.lastname: Detorie
authors.forename: Michelle
authors.initials: M
authors.lastname: Russell
authors.forename: Bob S
authors.initials: BS
authors.lastname: Carter
authors.forename: Kevin T
authors.initials: KT
authors.lastname: Murphy
authors.forename: Arno J
authors.initials: AJ
authors.lastname: Mundt
authors.forename: Clark
authors.initials: C
authors.lastname: Chen
authors.forename: Joshua D
authors.initials: JD
authors.lastname: Lawson
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000473:pathology / Q000601:surgery; D001932:Brain Neoplasms / Q000401:mortality / Q000473:pathology / Q000556:secondary* / Q000601:surgery*; D003199:Computer Systems; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000209:etiology; D016634:Radiosurgery / Q000379:methods*; D016019:Survival Analysis; D016896:Treatment Outcome