Positron emission tomography (11)C-methionine and survival in patients with low-grade gliomas.
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.
Ribom
D
D
Department of Neuroscience, Neurology, University Hospital, Uppsala, Sweden. dan.ribom@neurologi.uu.se
Eriksson
A
A
Hartman
M
M
Engler
H
H
Nilsson
A
A
Långström
B
B
Bolander
H
H
Bergström
M
M
Smits
A
A
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
D002250:Carbon Radioisotopes; D008715:Methionine