title: Management of atypical cranial meningiomas, part 1: predictors of recurrence and the role of adjuvant radiation after gross total resection.
abstract: BACKGROUND
  Indications for external beam radiation therapy (EBRT) for atypical meningiomas (AMs) remain unclear.
  
  
  OBJECTIVE
  To analyze features associated with recurrence in AM patients after gross total resection (GTR) and to assess the relative benefit of EBRT in a retrospective cohort study.
  
  
  METHODS
  One hundred fifty-one primary AMs after GTR (88 female patients; median follow-up, 45.0 months) were examined for possible predictors of recurrence (age, sex, location, volume, bone involvement, brain invasion). The Fisher exact and Wilcoxon rank-sum tests were used to analyze the association between these predictors and use of EBRT. The impact on recurrence for these predictors and EBRT was analyzed with Kaplan-Meier and Cox regression.
  
  
  RESULTS
  Of 151 patients, 13 (8.6%) experienced recurrence after GTR (median, 47.0 months). Multivariate analysis identified elevated mitotic index (P = .007) and brain invasion (P = .002) as predictors of recurrence. Larger volume (P = .96) was not associated with recurrence but was more likely to prompt EBRT (P = .001). Recurrences occurred in 11 of 112 with GTR (9.8%; median, 44 months) and 2 of 39 with GTR/EBRT (5.1%; median, 133 months). The 2-, 5-, and 10-year progression-free survival rates after GTR vs GTR/EBRT were 97%, 86%, and 68% vs 100%, 100%, and 78%. Kaplan-Meier analysis demonstrated no difference in progression-free survival or overall survival after GTR vs GTR/EBRT (P = .8, P > .99).
  
  
  CONCLUSIONS
  Brain invasion and high mitotic rates may predict recurrence. After GTR of AMs, EBRT appears not to affect progression-free survival and overall survival, suggesting that observation rather than EBRT may be indicated after GTR.
authors.affiliation: ‡Washington University School of Medicine, St. Louis, Missouri; and §Department of Neurosurgery, ¶Pathology and Immunology, and ‖Radiation Oncology, Washington University, St. Louis, Missouri.
authors.forename: Sam Q
authors.initials: SQ
authors.lastname: Sun
authors.forename: Albert H
authors.initials: AH
authors.lastname: Kim
authors.forename: Chunyu
authors.initials: C
authors.lastname: Cai
authors.forename: Rory K J
authors.initials: RK
authors.lastname: Murphy
authors.forename: Todd
authors.initials: T
authors.lastname: DeWees
authors.forename: Peter
authors.initials: P
authors.lastname: Sylvester
authors.forename: Ralph G
authors.initials: RG
authors.lastname: Dacey
authors.forename: Robert L
authors.initials: RL
authors.lastname: Grubb
authors.forename: Keith M
authors.initials: KM
authors.lastname: Rich
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Zipfel
authors.forename: Joshua L
authors.initials: JL
authors.lastname: Dowling
authors.forename: Eric C
authors.initials: EC
authors.lastname: Leuthardt
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Leonard
authors.forename: John
authors.initials: J
authors.lastname: Evans
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Simpson
authors.forename: Clifford G
authors.initials: CG
authors.lastname: Robinson
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Perrin
authors.forename: Jiayi
authors.initials: J
authors.lastname: Huang
authors.forename: Michael R
authors.initials: MR
authors.lastname: Chicoine
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000601:surgery; D015331:Cohort Studies; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008577:Meningeal Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D008579:Meningioma / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D008875:Middle Aged; D015999:Multivariate Analysis; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery; D018714:Radiotherapy, Adjuvant; D012189:Retrospective Studies; D016896:Treatment Outcome