title: Adjuvant Radiosurgery Versus Serial Surveillance Following Subtotal Resection of Atypical Meningioma: A Systematic Analysis.
abstract: BACKGROUND
  Atypical meningioma (AM) is an aggressive subtype of meningioma associated with a high recurrence rates (RR) following surgical resection. Recent studies have compared outcomes of various treatment strategies, but advantages of adjuvant radiosurgery (ARS) over serial surveillance (SS) following subtotal resection (STR) remain unclear. To further elucidate this issue, we systematically analyzed the current literature on AM and compared outcomes of ARS versus SS after STR.
  
  
  METHODS
  Embase, PubMed, and Cochrane databases were queried using relevant search terms. Retrospective case series that described patients with AM treated with ARS and SS after STR were included. Tests of proportions were performed to detect significant variations in RR, 5-year progression-free survival (PFS), and 5-year overall survival (OS) between the treatment strategies (ARS vs. SS) and among individual studies.
  
  
  RESULTS
  A total of 619 patients (263 in the ARS group and 356 in the SS group) were identified. Mean RR, 5-year PFS, and 5-year OS were 53.5%, 50.3%, and 74.9%, respectively, for ARS versus 89.8%, 19.1%, and 89.8% for SS. RR differed between treatment strategies and ARS studies (P < 0.001), and 5-year PFS differed among treatment strategies, ARS, and SS studies (P < 0.001, P = 0.007, and P < 0.001, respectively).
  
  
  CONCLUSIONS
  The data presented here show significant differences in RR and 5-year PFS between ARS and SS, suggesting a potential benefit of ARS. As our understanding of the clinical outcomes of various treatment strategies for AM increases, we also move closer to integrating modalities, such as radiosurgery, into management guidelines.
authors.affiliation: Department of Neurosurgery, University of California, Los Angeles, Los Angeles, California, USA.
authors.forename: Carlito
authors.initials: C
authors.lastname: Lagman
authors.affiliation: Department of Neurosurgery, University of California, Los Angeles, Los Angeles, California, USA.
authors.forename: Nikhilesh S
authors.initials: NS
authors.lastname: Bhatt
authors.affiliation: Department of Neurosurgery, University of California, Los Angeles, Los Angeles, California, USA.
authors.forename: Seung J
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: Department of Neurosurgery, University of California, Los Angeles, Los Angeles, California, USA.
authors.forename: Timothy T
authors.initials: TT
authors.lastname: Bui
authors.affiliation: Department of Neurosurgery, University of California, Los Angeles, Los Angeles, California, USA.
authors.forename: Lawrance K
authors.initials: LK
authors.lastname: Chung
authors.affiliation: Department of Neurosurgery, University of California, Los Angeles, Los Angeles, California, USA.
authors.forename: Brittany L
authors.initials: BL
authors.lastname: Voth
authors.affiliation: Department of Neurosurgery, University of California, Los Angeles, Los Angeles, California, USA.
authors.forename: Natalie E
authors.initials: NE
authors.lastname: Barnette
authors.affiliation: Department of Neurosurgery, University of California, Los Angeles, Los Angeles, California, USA.
authors.forename: Nader
authors.initials: N
authors.lastname: Pouratian
authors.affiliation: Department of Radiation Oncology, University of California, Los Angeles, Los Angeles, California, USA.
authors.forename: Percy
authors.initials: P
authors.lastname: Lee
authors.affiliation: Department of Radiation Oncology, University of California, Los Angeles, Los Angeles, California, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Selch
authors.affiliation: Department of Neurosurgery, University of California, Los Angeles, Los Angeles, California, USA; Department of Radiation Oncology, University of California, Los Angeles, Los Angeles, California, USA; Jonsson Comprehensive Cancer Center, University of California, Los Angeles, Los Angeles, California, USA.
authors.forename: Tania
authors.initials: T
authors.lastname: Kaprealian
authors.affiliation: Department of Radiation Oncology, University of California, Los Angeles, Los Angeles, California, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Chin
authors.affiliation: Department of Epidemiology, University of California, Los Angeles, Los Angeles, California, USA.
authors.forename: David L
authors.initials: DL
authors.lastname: McArthur
authors.affiliation: Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Debraj
authors.initials: D
authors.lastname: Mukherjee
authors.affiliation: Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Chirag G
authors.initials: CG
authors.lastname: Patil
authors.affiliation: Department of Neurosurgery, University of California, Los Angeles, Los Angeles, California, USA; Department of Radiation Oncology, University of California, Los Angeles, Los Angeles, California, USA; Jonsson Comprehensive Cancer Center, University of California, Los Angeles, Los Angeles, California, USA. Electronic address: iyang@mednet.ucla.edu.
authors.forename: Isaac
authors.initials: I
authors.lastname: Yang
mesh_terms: D006801:Humans; D008577:Meningeal Neoplasms / Q000175:diagnosis / Q000532:radiotherapy* / Q000601:surgery*; D008579:Meningioma / Q000175:diagnosis / Q000532:radiotherapy* / Q000601:surgery*; D018714:Radiotherapy, Adjuvant / Q000379:methods* / Q000592:standards; D012189:Retrospective Studies; D018571:Sentinel Surveillance; D057832:Watchful Waiting / Q000379:methods* / Q000592:standards
keywords: Adjuvant radiosurgery; Atypical meningioma; Serial surveillance