title: Low grade gliomas in eloquent locations - implications for surgical strategy, survival and long term quality of life.
abstract: BACKGROUND
  Surgical management of suspected LGG remains controversial. A key factor when deciding a surgical strategy is often the tumors' perceived relationship to eloquent brain regions
  
  
  OBJECTIVE
  To study the association between tumor location, survival and long-term health related quality of life (HRQL) in patients with supratentorial low-grade gliomas (LGG).
  
  
  METHODS
  Adults (≥18 years) operated due to newly diagnosed LGG from 1998 through 2009 included from two Norwegian university hospitals. After review of initial histopathology, 153 adults with supratentorial WHO grade II LGG were included in the study. Tumors' anatomical location and the relationship to eloquent regions were graded. Survival analysis was adjusted for known prognostic factors and the initial surgical procedure (biopsy or resection). In long-term survivors, HRQL was assessed with disease specific questionnaires (EORTC QLQ-C30 and BN20) as well as a generic questionnaire (EuroQol 5D).
  
  
  RESULTS
  There was a significant association between eloquence and survival (log-rank, p<0.001). The estimated 5-year survival was 77% in non-eloquent tumors, 71% in intermediate located tumors and 54% in eloquent tumors. In the adjusted analysis the hazard ratio of increasing eloquence was 1.5 (95% CI 1.1-2.0, p = 0.022). There were no differences in HRQL between patients with eloquent and non-eloquent tumors. The most frequent self-reported symptoms were related to fatigue, cognition, and future uncertainty.
  
  
  CONCLUSIONS
  Eloquently located LGGs are associated with impaired survival compared to non-eloquently located LGG, but in long-term survivors HRQL is similar. Although causal inference from observational data should be done with caution, the findings illuminate the delicate balance in surgical decision making in LGGs, and add support to the probable survival benefits of aggressive surgical strategies, perhaps also in eloquent locations.
authors.affiliation: Department of Neurosurgery, St.Olavs University Hospital, Trondheim, Norway. asgeir.s.jakola@ntnu.no
authors.forename: Asgeir S
authors.initials: AS
authors.lastname: Jakola
authors.forename: Geirmund
authors.initials: G
authors.lastname: Unsgård
authors.forename: Kristin S
authors.initials: KS
authors.lastname: Myrmel
authors.forename: Roar
authors.initials: R
authors.lastname: Kloster
authors.forename: Sverre H
authors.initials: SH
authors.lastname: Torp
authors.forename: Sigurd
authors.initials: S
authors.lastname: Lindal
authors.forename: Ole
authors.initials: O
authors.lastname: Solheim
mesh_terms: D000328:Adult; D001932:Brain Neoplasms / Q000473:pathology* / Q000601:surgery*; D005260:Female; D005910:Glioma / Q000473:pathology* / Q000601:surgery*; D006801:Humans; D008297:Male; D060787:Neoplasm Grading; D011788:Quality of Life; D011795:Surveys and Questionnaires; D016019:Survival Analysis; D017741:Survivors