title: Prognostic value of residual fluorescent tissue in glioblastoma patients after gross total resection in 5-aminolevulinic Acid-guided surgery.
abstract: BACKGROUND
  There is evidence in the literature supporting that fluorescent tissue signal in fluorescence-guided surgery extends farther than tissue highlighted in gadolinium in T1 sequence magnetic resonance imaging (MRI), which is the standard to quantify the extent of resection.
  
  
  OBJECTIVE
  To study whether the presence of residual fluorescent tissue after surgery carries a different prognosis for glioblastoma (GBM) cases with complete resection confirmed by MRI.
  
  
  METHODS
  A retrospective review in our center found 118 consecutive patients with high-grade gliomas operated on with the use of fluorescence-guided surgery with 5-aminolevulinic acid. Within that series, the 52 patients with newly diagnosed GBM and complete resection of enhancing tumor (CRET) in early MRI were selected for analysis. We studied the influence of residual fluorescence in the surgical field on overall survival and neurological complication rate. Multivariate analysis included potential relevant factors: age, Karnofsky Performance Scale, O-methylguanine methyltransferase methylation promoter status, tumor eloquent location, preoperative tumor volume, and adjuvant therapy.
  
  
  RESULTS
  The median overall survival was 27.0 months (confidence interval = 22.4-31.6) in patients with nonresidual fluorescence (n = 25) and 17.5 months (confidence interval = 12.5-22.5) for the group with residual fluorescence (n = 27) (P = .015). The influence of residual fluorescence was maintained in the multivariate analysis with all covariables, hazard ratio = 2.5 (P = .041). The neurological complication rate was 18.5% in patients with nonresidual fluorescence and 8% for the group with residual fluorescence (P = .267).
  
  
  CONCLUSIONS
  GBM patients with CRET in early MRI and no fluorescent residual tissue had longer overall survival than patients with CRET and residual fluorescent tissue.
authors.affiliation: Department of Neurosurgery, Clínica Universidad de Navarra, Pamplona, Spain. gaorzaiz@unav.es
authors.forename: Guillermo
authors.initials: G
authors.lastname: Aldave
authors.forename: Sonia
authors.initials: S
authors.lastname: Tejada
authors.forename: Eva
authors.initials: E
authors.lastname: Pay
authors.forename: Miguel
authors.initials: M
authors.lastname: Marigil
authors.forename: Bartolomé
authors.initials: B
authors.lastname: Bejarano
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Idoate
authors.forename: Ricardo
authors.initials: R
authors.lastname: Díez-Valle
mesh_terms: D000622:Aminolevulinic Acid; D001932:Brain Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D005260:Female; D005456:Fluorescent Dyes; D005909:Glioblastoma / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000379:methods; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies
chemical_list: D005456:Fluorescent Dyes; D000622:Aminolevulinic Acid