title: Radiation therapy for glioblastoma: Executive summary of an American Society for Radiation Oncology Evidence-Based Clinical Practice Guideline.
abstract: OBJECTIVE
  To present evidence-based guidelines for radiation therapy in treating glioblastoma not arising from the brainstem.
  
  
  METHODS
  The American Society for Radiation Oncology (ASTRO) convened the Glioblastoma Guideline Panel to perform a systematic literature review investigating the following: (1) Is radiation therapy indicated after biopsy/resection of glioblastoma and how does systemic therapy modify its effects? (2) What is the optimal dose-fractionation schedule for external beam radiation therapy after biopsy/resection of glioblastoma and how might treatment vary based on pretreatment characteristics such as age or performance status? (3) What are ideal target volumes for curative-intent external beam radiation therapy of glioblastoma? (4) What is the role of reirradiation among glioblastoma patients whose disease recurs following completion of standard first-line therapy? Guideline recommendations were created using predefined consensus-building methodology supported by ASTRO-approved tools for grading evidence quality and recommendation strength.
  
  
  RESULTS
  Following biopsy or resection, glioblastoma patients with reasonable performance status up to 70 years of age should receive conventionally fractionated radiation therapy (eg, 60 Gy in 2-Gy fractions) with concurrent and adjuvant temozolomide. Routine addition of bevacizumab to this regimen is not recommended. Elderly patients (≥70 years of age) with reasonable performance status should receive hypofractionated radiation therapy (eg, 40 Gy in 2.66-Gy fractions); preliminary evidence may support adding concurrent and adjuvant temozolomide to this regimen. Partial brain irradiation is the standard paradigm for radiation delivery. A variety of acceptable strategies exist for target volume definition, generally involving 2 phases (primary and boost volumes) or 1 phase (single volume). For recurrent glioblastoma, focal reirradiation can be considered in younger patients with good performance status.
  
  
  CONCLUSIONS
  Radiation therapy occupies an integral role in treating glioblastoma. Whether and how radiation therapy should be applied depends on characteristics specific to tumor and patient, including age and performance status.
authors.affiliation: Department of Radiation Oncology, Group Health Physicians, Seattle, Washington. Electronic address: acabrera@post.harvard.edu.
authors.forename: Alvin R
authors.initials: AR
authors.lastname: Cabrera
authors.affiliation: Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina.
authors.forename: John P
authors.initials: JP
authors.lastname: Kirkpatrick
authors.affiliation: Department of Radiation Oncology, University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: John B
authors.initials: JB
authors.lastname: Fiveash
authors.affiliation: Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Helen A
authors.initials: HA
authors.lastname: Shih
authors.affiliation: Department of Radiation Oncology, M.D. Anderson Cancer Center, Houston, Texas.
authors.forename: Eugene J
authors.initials: EJ
authors.lastname: Koay
authors.affiliation: Department of Radiation Oncology, Blanchard Valley Regional Health Center, Findlay, Ohio.
authors.forename: Stephen
authors.initials: S
authors.lastname: Lutz
authors.affiliation: Department of Radiation Oncology, University of Colorado Health, Fort Collins, Colorado.
authors.forename: Joshua
authors.initials: J
authors.lastname: Petit
authors.affiliation: Department of Radiation Oncology, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Samuel T
authors.initials: ST
authors.lastname: Chao
authors.affiliation: Department of Radiation Oncology, M.D. Anderson Cancer Center, Houston, Texas.
authors.forename: Paul D
authors.initials: PD
authors.lastname: Brown
authors.affiliation: Brain Tumor and Neuro-Oncology Center, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Michael
authors.initials: M
authors.lastname: Vogelbaum
authors.affiliation: Center for Neuro-Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts.
authors.forename: David A
authors.initials: DA
authors.lastname: Reardon
authors.affiliation: Department of Radiation Oncology, Ohio State University, Columbus, Ohio.
authors.forename: Arnab
authors.initials: A
authors.lastname: Chakravarti
authors.affiliation: Center for Neuro-Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts.
authors.forename: Patrick Y
authors.initials: PY
authors.lastname: Wen
authors.affiliation: Department of Radiation Oncology, Keck School of Medicine, University of Southern California, Los Angeles, California.
authors.forename: Eric
authors.initials: E
authors.lastname: Chang
mesh_terms: D001932:Brain Neoplasms / Q000532:radiotherapy*; D019583:Dose Fractionation, Radiation; D005909:Glioblastoma / Q000532:radiotherapy*; D017408:Guidelines as Topic; D006801:Humans; D008297:Male; D011446:Prospective Studies; D014481:United States