title: WHO grade 1 meningioma recurrence: Are location and Simpson grade still relevant?
abstract: OBJECTIVE
  To examine whether Simpson grade and pathology location are still predictors of recurrence/progression free survival (RPFS) in WHO grade 1 cranial meningiomas.
  
  
  METHODS
  A retrospective case series of all WHO grade 1 cranial meningiomas undergoing surgical resection at our institution between 2002 to 2007 was performed. Demographic and outcome data included: Simpson grade, extent of resection [gross total (Simpson 1-3) and sub total (Simpson 4-5)], tumour location, timing of post-operative imaging and outpatient review, time to recurrence and subsequent management. Statistical analysis was by Kaplan-Meier survival curves.
  
  
  RESULTS
  145 cases were included of which 75% were female, with an overall median age of 55 years. 24% had parasagittal, 23% convexity and 53% skull base meningioma. 21% had a grade 1 Simpson resection, 43% grade 2, 35% grade 4 and 1% grade 5. The median follow up period was 60 months with a median 5.5 outpatient appointments and 5 post-operative imaging studies. 10 cases (6.9%) had recurrence/progression at a median period of 42 months. Of these, 4 remained under active surveillance, 3 received stereotactic radiosurgery and 3 were treated with fractionated radiotherapy. 5 year recurrence/progression free survival (RPFS) for Simpson grade 1 was 96.8%, 2: 100%, 4: 82.4% and 5: 0%. Simpson grade (p=0.01) and gross total/sub total resection (p=0.001) were significant predictors of RPFS. Meningioma location was not a significant predictor of RPFS (p-value 0.836).
  
  
  CONCLUSIONS
  Simpson grade remains a significant predictor of RPFS in WHO grade 1 meningioma surgery. However, tumour location was not significant in this series. We advocate different post-operative imaging surveillance protocols depending on gross total or sub total surgical resection.
authors.affiliation: The Walton Centre NHS Foundation Trust, Lower Lane, Liverpool L9 7LJ, United Kingdom. Electronic address: matgallagher@doctors.org.uk.
authors.forename: Mathew J
authors.initials: MJ
authors.lastname: Gallagher
authors.affiliation: The Walton Centre NHS Foundation Trust, Lower Lane, Liverpool L9 7LJ, United Kingdom; Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom. Electronic address: michael.jenkinson@liverpool.ac.uk.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Jenkinson
authors.affiliation: The Walton Centre NHS Foundation Trust, Lower Lane, Liverpool L9 7LJ, United Kingdom. Electronic address: Andrew.brodbelt@thewaltoncentre.nhs.uk.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Brodbelt
authors.affiliation: The Walton Centre NHS Foundation Trust, Lower Lane, Liverpool L9 7LJ, United Kingdom. Electronic address: Samantha.mills@thewaltoncentre.nhs.uk.
authors.forename: Samantha J
authors.initials: SJ
authors.lastname: Mills
authors.affiliation: The Walton Centre NHS Foundation Trust, Lower Lane, Liverpool L9 7LJ, United Kingdom. Electronic address: emmanuel.chavredakis@thewaltoncentre.nhs.uk.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Chavredakis
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008577:Meningeal Neoplasms / Q000175:diagnosis* / Q000401:mortality / Q000601:surgery; D008579:Meningioma / Q000175:diagnosis* / Q000401:mortality / Q000601:surgery; D008875:Middle Aged; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000401:mortality / Q000601:surgery; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D014944:World Health Organization; D055815:Young Adult
keywords: Location; Meningioma; Outcome; Recurrence; Simpson grade