Metabolic characterization of childhood brain tumors: comparison of 18F-fluorodeoxyglucose and 11C-methionine positron emission tomography

Cancer. 2002 Sep 15;95(6):1376-86. doi: 10.1002/cncr.10798.


Background: Positron emission tomography (PET) scans of primary brain tumors were performed in pediatric patients to examine whether metabolic characteristics could be used as an index of clinical aggressiveness.

Methods: Twenty-seven pediatric patients with untreated primary central nervous system neoplasms were studied with PET scans using 2-[(18)F] fluoro-2-deoxy-D-glucose (FDG) and/or L-[methyl-(11)C] methionine (MET). Metabolic characteristics as assessed with FDG and MET standardized uptake values (SUV) and SUV-to-normal brain ratios were compared with histopathology and selected histochemical features such as proliferation activity (Ki-67(MIB-1)) and apoptotic, vascular, and cell density indices. The median followup time was 43 months.

Results: The accumulation of both FDG and MET was significantly higher in high-grade than in low-grade tumors, but a considerable overlap was found. The accumulation of both tracers was associated positively with age. High-grade tumors showed higher proliferative activity and vascularity than the low-grade tumors. In univariate analysis, FDG-PET, MET-PET, and apoptotic index were independent predictors of event-free survival.

Conclusion: We found that both FDG and MET uptake in pediatric brain tumors are associated with malignancy grade. However, no clear limits of SUVs and SUV-to-normal brain ratios can be set between low-grade and high-grade tumors, which makes the assessment of malignancy grade using metabolic imaging with PET scan difficult in individual cases. Although FDG-PET and MET-PET do not compensate for histopathologic evaluation, they may give valuable additional information especially if invasive procedures to obtain histopathologic samples are not feasible.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Age Factors
  • Apoptosis
  • Brain Neoplasms / diagnostic imaging
  • Brain Neoplasms / metabolism*
  • Brain Neoplasms / mortality
  • Brain Neoplasms / pathology
  • Carbon Radioisotopes*
  • Child
  • Child, Preschool
  • Female
  • Fluorodeoxyglucose F18*
  • Humans
  • Infant
  • Male
  • Methionine*
  • Radiopharmaceuticals*
  • Tomography, Emission-Computed*


  • Carbon Radioisotopes
  • Radiopharmaceuticals
  • Fluorodeoxyglucose F18
  • Methionine