title: Insular gliomas and the role of intraoperative assistive technologies: Results from a volumetry-based retrospective cohort.
abstract: BACKGROUND
  In the field of Glioma surgery, there has been an increasing interest in the use of assistive technologies to overcome the difficulty of preserving brain function while improving surgical radicality. In most reports, tumor localization has seldom been considered a variable and the role of intraoperative adjuncts is yet to be determined for gliomas of the insula.
  
  
  OBJECTIVE
  To evaluate the efficacy of fluorescence-guided resection with 5-ALA, intraoperative neurophysiological monitoring (IOM), neuronavigation, and tractography in the Extent of Resection (EOR), functionality scores, overall survival (OS) and progression-free survival (PFS) in a retrospective cohort of insular gliomas.
  
  
  METHODS
  We reviewed all cases of insular tumors operated on at the Department of Neurosurgery, University Hospital of Tübingen - Germany, between May 2008 and November 2013. EOR was determined by volumetric analysis. Mann Whitney, Chi-square and Kaplan Meier functions were used for assessment of each technology's effect on primary and secondary outcomes.
  
  
  RESULTS
  28 cases (18 men (64%) and 10 women (36%); median age at diagnosis: 52.5 years, range 12 - 59) were considered eligible for analysis. High grade and low grade gliomas accounted for 20 (71%) and 8 (29%) cases, respectively. The most used technologies were IOM (64%) and Neuronavigation (68%). 5-ALA was the only technique associated with EOR ≥90% (p=0.05). Tractography determined improvement in the Karnofsky Performance Scale (50% vs. 5% cases improved, p=0.02). There was a positive association between the use of neuronavigation and overall survival (23 vs. 27.4 months, p=0.03), but the use of 5-ALA was associated with shorter OS (34.8 vs. 21.1 months, p=0.01) and PFS (24.4 vs. 11.8, p=0.01).
  
  
  CONCLUSIONS
  We demonstrate for the first time that for insular gliomas 5-ALA plays a role in achieving higher EOR, although this technology was associated with poor OS and PFS; also tractography and neuronavigation can be of great importance in the treatment of insular gliomas as they determined better functionality and OS in this study, respectively. Prospective studies with a more prominent sample and proper multivariate analysis will help determine the real benefit of these adjuncts in the setting of insular gliomas.
authors: Department of Neurology, University of São Paulo School of Medicine, São Paulo, Brazil.
authors: Breno José Alencar Pires
authors: BJ
authors: Barbosa
authors: Department of Neurosurgery, Eberhard Karls University, Tübingen, Germany.
authors: Artemisia
authors: A
authors: Dimostheni
authors: Department of Neurology, University of São Paulo School of Medicine, São Paulo, Brazil.
authors: Manoel Jacobsen
authors: MJ
authors: Teixeira
authors: Department of Neurosurgery, Eberhard Karls University, Tübingen, Germany.
authors: Marcos
authors: M
authors: Tatagiba
authors: Department of Neurology, University of São Paulo School of Medicine, São Paulo, Brazil; Department of Neurosurgery, Eberhard Karls University, Tübingen, Germany. Electronic address: lepski@usp.br.
authors: Guilherme
authors: G
authors: Lepski
mesh_terms: D000293:Adolescent; D000328:Adult; D000622:Aminolevulinic Acid; D001932:Brain Neoplasms / Q000601:surgery*; D002540:Cerebral Cortex / Q000601:surgery*; D002648:Child; D056324:Diffusion Tensor Imaging / Q000379:methods*; D018572:Disease-Free Survival; D005260:Female; D005910:Glioma / Q000601:surgery*; D006801:Humans; D064795:Intraoperative Neurophysiological Monitoring / Q000379:methods*; D017567:Karnofsky Performance Status; D008297:Male; D008875:Middle Aged; D038361:Neuronavigation / Q000379:methods*; D017063:Outcome Assessment, Health Care / Q000379:methods*; D017319:Photosensitizing Agents; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D017319:Photosensitizing Agents; D000622:Aminolevulinic Acid
keywords: 5-ALA; Functionality; Glioma; Insula; Intraoperative monitoring; Neuronavigation; Tractography