Initial experience with [18F]DPA-714 TSPO-PET to image inflammation in primary angiitis of the central nervous system.

Abstract

PURPOSE:

Primary angiitis of the central nervous system (PACNS) is a heterogeneous, rare, and poorly understood inflammatory disease. We aimed at non-invasive imaging of activated microglia/macrophages in patients with PACNS by PET-MRI targeting the translocator protein (TSPO) with [18F]DPA-714 to potentially assist differential diagnosis, therapy monitoring, and biopsy planning.

METHODS:

In total, nine patients with ischemic stroke and diagnosed or suspected PACNS underwent [18F]DPA-714-PET-MRI. Dynamic PET scanning was performed for 60 min after injection of 233 ± 19 MBq [18F]DPA-714, and MRI was simultaneously acquired.

RESULTS:

In two PACNS patients, [18F]DPA-714 uptake patterns exceeded MRI correlates of infarction, whereas uptake was confined to the infarct in four patients where initial suspicion of PACNS could not be confirmed. About three patients with PACNS or cerebral predominant lymphocytic vasculitis showed no or only faintly increased uptake. Short-term [18F]DPA-714-PET follow-up in a patient with PACNS showed reduced lesional [18F]DPA-714 uptake after anti-inflammatory treatment. Biopsy in the same patient pinpointed the source of tracer uptake to TSPO-expressing immune cells.

CONCLUSIONS:

[18F]DPA-714-PET imaging may facilitate the diagnosis and treatment monitoring of PACNS. Further studies are needed to fully understand the potential of TSPO-PET in deciphering the heterogeneity of the disease.

• Authors: Philipp Backhaus, Wolfgang Roll, Carolin Beuker, Bastian Zinnhardt, Robert Seifert, Christian Wenning, Michel Eisenblätter, Christian Thomas, Antje Schmidt-Pogoda, Daniel Strunk, Stefan Wagner, Andreas Faust, Frank Tüttelmann, Albrecht Röpke, Andreas H Jacobs, Walter Stummer, Heinz Wiendl, Sven G Meuth, Michael Schäfers, Oliver Grauer, Jens Minnerup
• Journal: European journal of nuclear medicine and molecular imaging (Eur J Nucl Med Mol Imaging) Vol. 47 Issue 9 Pg. 2131-2141 (08 2020) ISSN: 1619-7089 [Electronic] Germany
• PMID: 31960097 (Publication Type: Case Reports, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Fluorine Radioisotopes
• N,N-diethyl-2-(2-(4-(2-fluoroethoxy)phenyl)-5,7-dimethylpyrazolo(1,5-a)pyrimidin-3-yl)acetamide
• Pyrazoles
• Pyrimidines
• Receptors, GABA
• TSPO protein, human

Topics

• Fluorine Radioisotopes
• Humans
• Inflammation (diagnostic imaging)
• Positron-Emission Tomography
• Pyrazoles
• Pyrimidines
• Receptors, GABA
• Vasculitis, Central Nervous System