Dataset Information

¹⁸F-Fluciclovine (¹⁸F-FACBC) PET imaging of recurrent brain tumors.

ABSTRACT:

Purpose

The aim of our study was to investigate the efficacy of ¹⁸F-Fluciclovine brain PET imaging in recurrent gliomas, and to compare the utility of these images to that of contrast enhanced magnetic resonance imaging (MRI) and to [¹¹C-methyl]-L-methionine (¹¹C-Methionine) PET imaging. We also sought to gain insight into the factors affecting the uptake of ¹⁸F-FACBC in both tumors and normal brain, and specifically to evaluate how the uptake in these tissues varied over an extended period of time post injection.

Methods

Twenty-seven patients with recurrent or progressive primary brain tumor (based on clinical and MRI/CT data) were studied using dynamic ¹⁸F-Fluciclovine brain imaging for up to 4 h. Of these, 16 patients also had ¹¹C-Methionine brain scans. Visual findings, semi-quantitative analyses and pharmacokinetic modeling of a subset of the ¹⁸F-Fluciclovine images was conducted. The information derived from these analyses were compared to data from ¹¹C-Methionine and to contrast-enhanced MRI.

Results

¹⁸F-Fluciclovine was positive for all 27 patients, whereas contrast MRI was indeterminate for three patients. Tumor ¹⁸F-Fluciclovine SUVmax ranged from 1.5 to 10.5 (average: 4.5?±?2.3), while ¹¹C-Methionine's tumor SUVmax ranged from 2.2 to 10.2 (average: 5.0?±?2.2). Image contrast was higher with ¹⁸F-Fluciclovine compared to ¹¹C-Methionine (p?18F-Fluciclovine's lower background in normal brain tissue (0.5?±?0.2 compared to 1.3?±?0.4 for ¹¹C-Methionine). ¹⁸F-Fluciclovine uptake in both normal brain and tumors was well described by a simple one-compartment (three-parameter: V_b,k₁,k₂) model. Normal brain was found to approach transient equilibrium with a half-time that varied greatly, ranging from 1.5 to 8.3 h (mean 2.7?±?2.3 h), and achieving a consistent final distribution volume averaging 1.4?±?0.2 ml/cc. Tumors equilibrated more rapidly (t_1/2ranging from 4 to 148 min, average 57?±?51 min), with an average distribution volume of 3.2?±?1.1 ml/cc. A qualitative comparison showed that the rate of normal brain uptake of ¹¹C-Methionine was much faster than that of ¹⁸F-Fluciclovine.

Conclusion

Tumor uptake of ¹⁸F-Fluciclovine correlated well with the established brain tumor imaging agent ¹¹C-Methionine but provided significantly higher image contrast. ¹⁸F-Fluciclovine may be particularly useful when the contrast MRI is non-diagnostic. Based on the data gathered, we were unable to determine whether Fluciclovine uptake was due solely to recurrent tumor or if inflammation or other processes also contributed.

SUBMITTER: Michaud L

PROVIDER: S-EPMC7188736 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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18F-Fluciclovine (18F-FACBC) PET imaging of recurrent brain tumors.

Michaud Laure L Beattie B J BJ Akhurst T T Dunphy M M Zanzonico P P Finn R R Mauguen A A Schöder H H Weber W A WA Lassman A B AB Blasberg R R

European journal of nuclear medicine and molecular imaging 20190815 6

<h4>Purpose</h4>The aim of our study was to investigate the efficacy of 18F-Fluciclovine brain PET imaging in recurrent gliomas, and to compare the utility of these images to that of contrast enhanced magnetic resonance imaging (MRI) and to [11C-methyl]-L-methionine (11C-Methionine) PET imaging. We also sought to gain insight into the factors affecting the uptake of 18F-FACBC in both tumors and normal brain, and specifically to evaluate how the uptake ...[more]

PMID: 31418054

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