Glucose metabolic changes in nontumoral brain tissue of patients with brain tumor following radiotherapy: a preliminary study

J Comput Assist Tomogr. Sep-Oct 1996;20(5):709-14. doi: 10.1097/00004728-199609000-00004.

Abstract

Purpose: Our goal was to measure the effect of radiotherapy on the brain glucose metabolism of tumoral and nontumoral tissue of patients with brain malignancies.

Method: Fifteen patients with primary or metastatic brain tumors were studied with 2-deoxy-2-[18F]fluoro-D-glucose and PET prior to radiotherapy, and nine of them were rescanned 1 week after completing radiotherapy.

Results: Brain metabolism in patients (all brain regions except for tumoral and edematous tissue) was lower than that of matched controls (34.0 +/- 8.3 vs. 46.5 +/- 6.4 mumol/100 g/min; p < or = 0.0001). Five of the nine patients retested after radiotherapy showed decrements in tumor metabolism (47 +/- 10%; p < or = 0.05) and increases in brain metabolism (10 +/- 4%; p < or = 0.004), and the other four showed no changes in tumor or in brain metabolism. Radiotherapy-induced changes in tumor metabolism were negatively correlated with changes in brain metabolism (r = 0.85, p < or = 0.004), but not with changes in tumor volume (assessed with MR images).

Conclusion: The study indicates that radiotherapy-induced increases in metabolism of nontumoral tissue are secondary to decreased tumor metabolic activity and not just due to volume reduction.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Aged
  • Brain / metabolism*
  • Brain / radiation effects
  • Brain Neoplasms / diagnostic imaging
  • Brain Neoplasms / metabolism*
  • Brain Neoplasms / radiotherapy*
  • Deoxyglucose / analogs & derivatives
  • Female
  • Fluorine Radioisotopes
  • Fluorodeoxyglucose F18
  • Glucose / metabolism*
  • Humans
  • Male
  • Middle Aged
  • Radiotherapy Dosage
  • Tomography, Emission-Computed

Substances

  • Fluorine Radioisotopes
  • Fluorodeoxyglucose F18
  • Deoxyglucose
  • Glucose