title: Stereotactic Radiosurgery for Brainstem Metastases: An International Cooperative Study to Define Response and Toxicity.
abstract: To pool data across multiple institutions internationally and report on the cumulative experience of brainstem stereotactic radiosurgery (SRS).
  
  
  
  Data on patients with brainstem metastases treated with SRS were collected through the International Gamma Knife Research Foundation. Clinical, radiographic, and dosimetric characteristics were compared for factors prognostic for local control (LC) and overall survival (OS) using univariate and multivariate analyses.
  
  
  
  Of 547 patients with 596 brainstem metastases treated with SRS, treatment of 7.4% of tumors resulted in severe SRS-induced toxicity (grade ≥3, increased odds with increasing tumor volume, margin dose, and whole-brain irradiation). Local control at 12 months after SRS was 81.8% and was improved with increasing margin dose and maximum dose. Overall survival at 12 months after SRS was 32.7% and impacted by age, gender, number of metastases, tumor histology, and performance score.
  
  
  
  Our study provides additional evidence that SRS has become an option for patients with brainstem metastases, with an excellent benefit-to-risk ratio in the hands of experienced clinicians. Prior whole-brain irradiation increases the risk of severe toxicity in brainstem metastasis patients undergoing SRS.
authors.affiliation: Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia. Electronic address: daniel.trifiletti@gmail.com.
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Trifiletti
authors.affiliation: Department of Neurosurgery, Neurological Institute, Taipei Veteran General Hospital, Taipei, Taiwan, People's Republic of China.
authors.forename: Cheng-Chia
authors.initials: CC
authors.lastname: Lee
authors.affiliation: Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Kano
authors.affiliation: Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Cohen
authors.affiliation: Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: James
authors.initials: J
authors.lastname: Janopaul-Naylor
authors.affiliation: Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Michelle
authors.initials: M
authors.lastname: Alonso-Basanta
authors.affiliation: Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: John Y K
authors.initials: JYK
authors.lastname: Lee
authors.affiliation: Department of Radiation and Stereotactic Neurosurgery, Na Homolce Hospital, Prague, Czech Republic.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Simonova
authors.affiliation: Department of Radiation and Stereotactic Neurosurgery, Na Homolce Hospital, Prague, Czech Republic.
authors.forename: Roman
authors.initials: R
authors.lastname: Liscak
authors.affiliation: Department of Neurosurgery, New York University Lagone Medical Center, New York, New York.
authors.forename: Amparo
authors.initials: A
authors.lastname: Wolf
authors.affiliation: Department of Neurosurgery, New York University Lagone Medical Center, New York, New York.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Kvint
authors.affiliation: Department of Radiation Oncology, Beaumont Health System, Royal Oak, Michigan.
authors.forename: Inga S
authors.initials: IS
authors.lastname: Grills
authors.affiliation: Department of Radiation Oncology, Beaumont Health System, Royal Oak, Michigan.
authors.forename: Matthew
authors.initials: M
authors.lastname: Johnson
authors.affiliation: Department of Neurosurgery, Neurological Institute, Taipei Veteran General Hospital, Taipei, Taiwan, People's Republic of China.
authors.forename: Kang-Du
authors.initials: KD
authors.lastname: Liu
authors.affiliation: Department of Neurosurgery, Neurological Institute, Taipei Veteran General Hospital, Taipei, Taiwan, People's Republic of China.
authors.forename: Chung-Jung
authors.initials: CJ
authors.lastname: Lin
authors.affiliation: Division of Neurosurgery, Université de Sherbrooke, Centre de recherche du CHUS, Sherbrooke, Québec, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Mathieu
authors.affiliation: Division of Neurosurgery, Université de Sherbrooke, Centre de recherche du CHUS, Sherbrooke, Québec, Canada.
authors.forename: France
authors.initials: F
authors.lastname: Héroux
authors.affiliation: Department of Neurosurgery, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Danilo
authors.initials: D
authors.lastname: Silva
authors.affiliation: Department of Neurosurgery, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Mayur
authors.initials: M
authors.lastname: Sharma
authors.affiliation: Departments of Neurosurgery and Radiation Oncology, West Virginia University, Morgantown, West Virginia.
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Cifarelli
authors.affiliation: Departments of Neurosurgery and Radiation Oncology, West Virginia University, Morgantown, West Virginia.
authors.forename: Christopher N
authors.initials: CN
authors.lastname: Watson
authors.affiliation: Departments of Neurosurgery and Radiation Oncology, West Virginia University, Morgantown, West Virginia.
authors.forename: Joshua D
authors.initials: JD
authors.lastname: Hack
authors.affiliation: Department of Neurosurgery, New York University Lagone Medical Center, New York, New York.
authors.forename: John G
authors.initials: JG
authors.lastname: Golfinos
authors.affiliation: Department of Neurosurgery, New York University Lagone Medical Center, New York, New York.
authors.forename: Douglas
authors.initials: D
authors.lastname: Kondziolka
authors.affiliation: Department of Neurosurgery, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Gene
authors.initials: G
authors.lastname: Barnett
authors.affiliation: Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
authors.forename: L Dade
authors.initials: LD
authors.lastname: Lunsford
authors.affiliation: Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia; Department of Neurological Surgery, University of Virginia, Charlottesville, Virginia.
authors.forename: Jason P
authors.initials: JP
authors.lastname: Sheehan
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D020295:Brain Stem Neoplasms / Q000401:mortality / Q000532:radiotherapy* / Q000556:secondary*; D015984:Causality; D015897:Comorbidity; D016371:Cranial Irradiation; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D007391:International Cooperation; D008297:Male; D008875:Middle Aged; D011832:Radiation Injuries; D016634:Radiosurgery; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D012307:Risk Factors; D017678:Sex Distribution; D015996:Survival Rate; D016896:Treatment Outcome