title: Positron emission tomography (11)C-methionine and survival in patients with low-grade gliomas.
abstract: BACKGROUND
  Considerable numbers of patients with low-grade gliomas experience an early malignant course and may benefit from aggressive treatment. These patients are difficult to identify using established prognostic factors. A retrospective study was performed to determine whether the (11)C-methionine uptake in tumor is a survival factor in adult patients with supratentorial gliomas classified as World Health Organization Grade 2.
  
  
  METHODS
  The authors identified 89 patients with histologically confirmed low-grade gliomas in whom an (11)C-methionine positron emission tomography (PET) scan had been performed as part of the diagnostic tumor investigation from 1983 to 1998. Clinical data were collected, and the PET scans were re-evaluated according to a fixed protocol. The (11)C-methionine uptake in the tumor and relevant clinical parameters were entered into univariate and multivariate survival analyses.
  
  
  RESULTS
  At the end of the study, 49 patients (55.1%) had died. The median overall survival was 5.7 years. Low methionine uptake was significantly favorable in the multivariate survival analysis (P = 0.04) along with oligodendroglioma (P = 0.003). In the histologic subgroups, (11)C-methionine uptake was an important survival factor among patients with astrocytomas (P = 0.05) and oligodendrogliomas (P = 0.03). Tumor resection was a favorable prognostic factor in patients with high methionine uptake (P = 0.01) but not in patients with low uptake.
  
  
  CONCLUSIONS
  Baseline (11)C-methionine PET is a prognostic indicator in patients with low-grade gliomas. The results imply that PET is a valuable tool in the clinical management of these patients and may assist in the selection of patients for therapy.
authors.affiliation: Department of Neuroscience, Neurology, University Hospital, Uppsala, Sweden. dan.ribom@neurologi.uu.se
authors.forename: D
authors.initials: D
authors.lastname: Ribom
authors.forename: A
authors.initials: A
authors.lastname: Eriksson
authors.forename: M
authors.initials: M
authors.lastname: Hartman
authors.forename: H
authors.initials: H
authors.lastname: Engler
authors.forename: A
authors.initials: A
authors.lastname: Nilsson
authors.forename: B
authors.initials: B
authors.lastname: Långström
authors.forename: H
authors.initials: H
authors.lastname: Bolander
authors.forename: M
authors.initials: M
authors.lastname: Bergström
authors.forename: A
authors.initials: A
authors.lastname: Smits
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001254:Astrocytoma / Q000000981:diagnostic imaging / Q000401:mortality; D001932:Brain Neoplasms / Q000000981:diagnostic imaging* / Q000401:mortality*; D002250:Carbon Radioisotopes; D005260:Female; D005910:Glioma / Q000000981:diagnostic imaging* / Q000401:mortality*; D006801:Humans; D008297:Male; D008715:Methionine; D008875:Middle Aged; D009837:Oligodendroglioma / Q000000981:diagnostic imaging / Q000401:mortality; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate; D014055:Tomography, Emission-Computed
chemical_list: D002250:Carbon Radioisotopes; D008715:Methionine