Related Experiment Video
Updated: Oct 1, 2026
Fluorescence Molecular Tomography for In Vivo Imaging of Glioblastoma Xenografts
Published on: April 26, 2018
2-[(18)F]Fluoro-2-deoxyglucose and glucose uptake in malignant gliomas before and after radiotherapy: correlation
Alexander M Spence1, Mark Muzi, Michael M Graham
1Department of Neurology, University of Washington School of Medicine, Seattle, Washington 98195, USA. aspence@u.washington.edu
Purpose:
To examine whether quantitative 1-[(11)C]glucose- or 2-[(18)F]fluoro-2-deoxyglucose (FDG)-positron emission tomography performed before and/or after radiotherapy (RT) of malignant gliomas correlates with treatment outcome. Changes in metabolism between the start and finish of RT, and immediate post-RT studies have received little attention.
Experimental Design:
Adults with malignant gliomas were imaged within 2 weeks before and/or 2 weeks after RT. Four patients were imaged only before RT, 12 only after RT, and 14 both before and after RT. Each 1-[(11)C]glucose and FDG study included arterial plasma sampling. Kinetic parameters, glucose metabolic rate (MRGlc), and FDG metabolic rate (MRFDG) were estimated by an optimization program based on a three compartment, four rate constant model. Changes in MRGlc or MRFDG from pre-RT to post-RT were calculated for the 14 patients studied at both times. Overall survival was examined, and survival was computed relative to historical controls in matched prognostic classes.
Results:
Low pre-RT MRGlc (P < 0.02) or MRFDG (P < 0.03), or an increase from pre- to post-RT in MRGlc (P < 0.004) or MRFDG (P < 0.006) are correlating with longer survival (4 patients still alive). Strikingly, the post-RT studies (n = 26) showed no correlation between MRGlc or MRFDG and survival (P = 0.73 and P = 0.46 respectively).
Conclusions:
Low MRGlc or MRFDG before RT probably indicates less aggressive disease. An increase in MRGlc or MRFDG from pre- to post-RT in the tumors of patients with longer survival could be because of one or more of the following or other reasons: (a) apoptosis of tumor cells in response to RT requires energy; (b) decreased tumor cell density by the RT leaving normal cells with higher metabolism; or (c) inflammatory cells infiltrate and take up glucose or FDG where tumor cells are dying. Quantitative 1-[(11)C]glucose or FDG uptake in the early weeks post-RT correlates poorly with survival.
