Prognostic Implications of Total Hemispheric Glucose Metabolism Ratio in Cerebrocerebellar Diaschisis.

Abstract

Diaschisis denotes brain dysfunction remote from a focal brain lesion. We have quantified diaschisis and investigated its prognostic value in glioma. Methods: We compared 50 18F-FDG PET/CT studies collected prospectively from 14 patients with supratentorial glioma (5 men and 9 women; age range, 35-77 y) with 10 single scans from healthy controls (age range, 43-75 y). Dedicated 3-dimensional segmentation software was used to obtain total hemispheric glucose metabolic ratios (THGr) by dividing total hemispheric 18F-FDG uptake in each diaschitic hemisphere-that is, the ipsilateral cerebral hemisphere (THGr(Ce)) and the contralateral cerebellar hemisphere (THGr(Cb))-by its respective contralateral side. Receiver-operating-characteristic (ROC) analysis was performed to determine optimal cut-offs for combinations of THGr(Ce) and THGr(Cb). Two independent observers obtained data for reproducibility analysis, and THGr values were compared with qualitative assessment of diaschisis performed by a PET neuroimaging specialist. Results: Qualitative analysis confirmed cerebrocerebellar diaschisis in all glioblastoma PET studies performed within 1 y of death. Healthy subjects had significantly higher THGr(Ce) values (P = 0.0007) and THGr(Cb) values (P = 0.02) than glioblastoma patients. ROC analysis yielded diaschisis thresholds of 0.62 for THGr(Ce) and 0.84 for THGr (Cb). Qualitative assessment demonstrated cerebral diaschisis in 16 of 17 (94%) cases with THGr(Ce) below the determined threshold and cerebellar diaschisis in 25 of 26 (96%) cases with THGr(Cb) below the determined threshold. When both THGr(Ce) and THGr(Cb) were below the ROC threshold, the combined diaschisis measures had a positive predictive value for survival below 1 y of 100%. When one parameter was below the threshold, it had a positive predictive value of 75%, and when both parameters exceeded thresholds, the negative predictive value for survival above 1 y was 79%. Median interrater variability was 3.3% and 5.9% for THGr(Ce) and THGr(Cb), respectively. Conclusion: The THGr measures demonstrated diaschisis in the cerebrum and cerebellum of patients with glioma. Combined cerebrocerebellar diaschisis ratios with ROC thresholds for both forebrain and hindbrain had high negative and positive predictive values for survival for less than a year. The THGr method allows comparison of data obtained at different institutions and is now open for further validation in gliomas and other cerebral diseases.

• Authors: Eivind Antonsen Segtnan, Peter Grupe, Jens Ole Jarden, Oke Gerke, Jana Ivanidze, Sofie Bæk Christlieb, Caius Constantinescu, John Erling Pedersen, Sina Houshmand, Søren Hess, Mojtaba Zarei, Albert Gjedde, Abass Alavi, Poul F Høilund-Carlsen
• Journal: Journal of nuclear medicine : official publication, Society of Nuclear Medicine (J Nucl Med) Vol. 58 Issue 5 Pg. 768-773 (05 2017) ISSN: 1535-5667 [Electronic] United States
• PMID: 27789719 (Publication Type: Journal Article)
• Copyright: © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

Chemical References

• Biomarkers
• Radiopharmaceuticals
• Fluorodeoxyglucose F18
• Glucose

Topics

• Adult
• Aged
• Biomarkers (metabolism)
• Brain Neoplasms (diagnostic imaging, metabolism)
• Female
• Fluorodeoxyglucose F18 (pharmacokinetics)
• Glioma (diagnostic imaging, metabolism)
• Glucose (metabolism)
• Humans
• Male
• Middle Aged
• Observer Variation
• Positron-Emission Tomography
• Prognosis
• Radiopharmaceuticals (pharmacokinetics)
• Tissue Distribution