title: Survival rates in patients with low-grade glioma after intraoperative magnetic resonance image guidance.
abstract: BACKGROUND
  No age-adjusted or histologic-adjusted assessments of the association between extent of resection and risk of either recurrence or death exist for neurosurgical patients who undergo resection of low-grade glioma using intraoperative magnetic resonance image (MRI) guidance.
  
  
  METHODS
  The current data included 156 patients who underwent surgical resection of a unifocal, supratentorial, low-grade glioma in the MRI suite at Brigham and Women's Hospital between January 1, 1997, and January 31, 2003. Estimates of disease-free and overall survival probabilities were calculated using Kaplan-Meier methodology. The association between extent of resection and these probabilities was measured using a Cox proportional hazards model. Observed death rates were compared with the expected death rate using age-specific and histologic-specific survival rates obtained from the Surveillance, Epidemiology, and End Results Registry.
  
  
  RESULTS
  Patients who underwent subtotal resection were at 1.4 times the risk of disease recurrence (95% confidence interval [95% CI], 0.7-3.1) and at 4.9 times the risk of death (95% CI, 0.61-40.0) relative to patients who underwent gross total resection. The 1-year, 2-year, and 5-year age-adjusted and histologic-adjusted death rates for patients who underwent surgical resection using intraoperative MRI guidance were 1.9% (95% CI, 0.3-4.2%), 3.6% (95% CI, 0.4-6.7%), and 17.6% (95% CI, 5.9-29.3%), respectively: significantly lower than the rates reported using national data bases.
  
  
  CONCLUSIONS
  The data from the current study suggested a possible association between surgical resection and survival for neurosurgical patients who underwent surgery for low-grade glioma under intraoperative MRI guidance. Further study within the context of a large, prospective, population-based project will be needed to confirm these findings.
authors.affiliation: Department of Neurosurgery, Brigham and Women's Hospital, Boston, Massachusetts, USA. elizabeth.claus@yale.edu
authors.forename: Elizabeth B
authors.initials: EB
authors.lastname: Claus
authors.forename: Andres
authors.initials: A
authors.lastname: Horlacher
authors.forename: Liangge
authors.initials: L
authors.lastname: Hsu
authors.forename: Richard B
authors.initials: RB
authors.lastname: Schwartz
authors.forename: Donna
authors.initials: D
authors.lastname: Dello-Iacono
authors.forename: Florian
authors.initials: F
authors.lastname: Talos
authors.forename: Ferenc A
authors.initials: FA
authors.lastname: Jolesz
authors.forename: Peter M
authors.initials: PM
authors.lastname: Black
mesh_terms: D000328:Adult; D001932:Brain Neoplasms / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D015331:Cohort Studies; D016001:Confidence Intervals; D005260:Female; D005910:Glioma / Q000175:diagnosis / Q000401:mortality* / Q000601:surgery*; D006801:Humans; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods; D009364:Neoplasm Recurrence, Local / Q000401:mortality* / Q000473:pathology; D009367:Neoplasm Staging; D019635:Neurosurgical Procedures / Q000379:methods; D011183:Postoperative Complications; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D018709:Statistics, Nonparametric; D016019:Survival Analysis; D016896:Treatment Outcome