title: Prognostic significance of contrast-enhancing low-grade gliomas in adults and a review of the literature.
abstract: OBJECTIVE
  Survival and tumor recurrence for patients with low-grade gliomas is heterogeneous, with reported survival and recurrence times varying by several months to years. The prognostic implications of a contrast-enhancing low-grade glioma remain less well understood.
  
  
  METHODS
  We retrospectively reviewed all adult patients who underwent a craniotomy for a hemispheric low-grade glioma (WHO grade II) from 1996 to 2006 at a single institution. Multivariate proportional hazards regression analysis was used to identify independent associations with survival, recurrence and malignant degeneration. Furthermore, a review of the literature for all works on low-grade gliomas and contrast enhancement was conducted.
  
  
  RESULTS
  One hundred eighty-nine patients (87 fibrillary astrocytomas, 89 oligodendrogliomas and 13 mixed gliomas) were available for analysis, with 64 (34%) and 125 (66%) contrast-enhancing and non-enhancing tumors, respectively. There were no significant differences in clinical and treatment-related variables between patients with and without contrast enhancement. After multivariate analysis, contrast enhancement was independently associated with decreased survival (p=0.006) and increased recurrence (p=0.04) and trended toward significance with malignant degeneration (p=0.15). Five-year overall survival, progression-free survival and malignancy-free survival rates for patients with enhancement versus patients without enhancement were 70 versus 85% (p=0.002), 32 versus 49% (p=0.008) and 74 versus 90% (p=0.002), respectively. The review of the literature identified 14 works that fit our criteria. The majority of these published works had design-related limitations including small population size as well as the inclusion of non-WHO grade II gliomas, pediatric patients and patient undergoing biopsy.
  
  
  CONCLUSIONS
  This study may provide insights into risk stratifying patients with low-grade gliomas and most specifically those that contrast enhance.
authors.affiliation: Department of Neurosurgery, Johns Hopkins School of Medicine, Baltimore, MD 21231, USA.
authors.forename: Kaisorn L
authors.initials: KL
authors.lastname: Chaichana
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: McGirt
authors.forename: Ashwini
authors.initials: A
authors.lastname: Niranjan
authors.forename: Alessandro
authors.initials: A
authors.lastname: Olivi
authors.forename: Peter C
authors.initials: PC
authors.lastname: Burger
authors.forename: Alfredo
authors.initials: A
authors.lastname: Quinones-Hinojosa
mesh_terms: D000328:Adult; D001254:Astrocytoma / Q000453:epidemiology / Q000473:pathology; D001932:Brain Neoplasms / Q000145:classification / Q000453:epidemiology / Q000473:pathology*; D003287:Contrast Media; D003399:Craniotomy; D005260:Female; D005910:Glioma / Q000145:classification / Q000453:epidemiology / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology; D009364:Neoplasm Recurrence, Local; D009837:Oligodendroglioma / Q000453:epidemiology / Q000473:pathology; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D015996:Survival Rate
chemical_list: D003287:Contrast Media