[F-18]Fluciclovine PET discrimination between high- and low-grade gliomas

• Type of Material: Article
• Authors: Ephraim Edward Parent, Emory University; Marc Benayoun, Massachusetts General Hospital; Ijeoma Ibeanu, Texas Tech University; Jeffrey James Olson, Emory University; Constantinos G. Hadjipanayis, Mount Sinai Beth Israel; Daniel J Brat, Emory University; Vikram Adhikarla, City of Hope National Medical Center; Jonathon A Nye, Emory University; David M Schuster, Emory University; Mark Goodman, Emory University
• Language: English
• Date: 2018-07-25
• Publisher: BioMed Central
• Publication Version: Final Published Version
• Copyright Statement: © 2018, The Author(s).
• License: Creative Commons Attribution 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1186/s13550-018-0415-3
• Title of Journal or Parent Work: EJNMMI Research
• ISSN: 2191-219X
• Volume: 8
• Issue: 1
• Start Page: 67
• End Page: 67
• Grant/Funding Information: Fluciclovine cassettes were provided by Blue Earth Diagnostics Limited.; This work was supported in part by a National Institutes of Health grant (R01 5RO1CA121320 to MMG).
• Keywords: Life Sciences & Biomedicine; BRAIN-TUMORS; Radiology, Nuclear Medicine & Medical Imaging; TRANSPORT MECHANISMS; Glioma; UPTAKE KINETICS; Science & Technology; F-18-DOPA; F-18-fluciclovine; ACID; Amino acid; PROSTATE-CANCER; PET; TREATMENT RESPONSE; CELLS; LAT1; FET PET
• Research Categories: Health Sciences, Radiology; Health Sciences, Pathology

Abstract

Background: The ability to accurately and non-invasively distinguish high-grade glioma from low-grade glioma remains a challenge despite advances in molecular and magnetic resonance imaging. We investigated the ability of fluciclovine (18F) PET as a means to identify and distinguish these lesions in patients with known gliomas and to correlate uptake with Ki-67. Results: Sixteen patients with a total of 18 newly diagnosed low-grade gliomas (n = 6) and high grade gliomas (n = 12) underwent fluciclovine PET imaging after histopathologic assessment. Fluciclovine PET analysis comprised tumor SUVmaxand SUVmean, as well as metabolic tumor thresholds (1.3*, 1.6*, 1.9*) to normal brain background (TBmax, and TBmean). Comparison was additionally made to the proliferative status of the tumor as indicated by Ki-67 values. Fluciclovine uptake greater than normal brain parenchyma was found in all lesions studied. Time activity curves demonstrated statistically apparent flattening of the curves for both high-grade gliomas and low-grade gliomas starting 30 min after injection, suggesting an influx/efflux equilibrium. The best semiquantitative metric in discriminating HGG from LGG was obtained utilizing a metabolic 1 tumor threshold of 1.3* contralateral normal brain parenchyma uptake to create a tumor: background (TBmean1.3) cutoff of 2.15 with an overall sensitivity of 97.5% and specificity of 95.5%. Additionally, using a SUVmax> 4.3 cutoff gave a sensitivity of 90.9% and specificity of 97.5%. Tumor SUVmeanand tumor SUVmaxas a ratio to mean normal contralateral brain were both found to be less relevant predictors of tumor grade. Both SUVmax(R = 0.71, p = 0.0227) and TBmean(TBmean1.3: R = 0.81, p = 0.00081) had a high correlation with the tumor proliferative index Ki-67. Conclusions: Fluciclovine PET produces high-contrast images between both low-grade and high grade gliomas and normal brain by visual and semiquantitative analysis. Fluciclovine PET appears to discriminate between low-grade glioma and high-grade glioma, but must be validated with a larger sample size.