Cortical [ 18 F]PI-2620 Binding Differentiates Corticobasal Syndrome Subtypes

Mov Disord. 2021 Sep;36(9):2104-2115. doi: 10.1002/mds.28624. Epub 2021 May 5.

Abstract

Background: Corticobasal syndrome is associated with cerebral protein aggregates composed of 4-repeat (~50% of cases) or mixed 3-repeat/4-repeat tau isoforms (~25% of cases) or nontauopathies (~25% of cases).

Objectives: The aim of this single-center study was to investigate the diagnostic value of the tau PET-ligand [18 F]PI-2620 in patients with corticobasal syndrome.

Methods: Forty-five patients (71.5 ± 7.6 years) with corticobasal syndrome and 14 age-matched healthy controls underwent [18 F]PI-2620-PET. Beta-amyloid status was determined by cerebral β-amyloid PET and/or CSF analysis. Subcortical and cortical [18 F]PI-2620 binding was quantitatively and visually compared between β-amyloid-positive and -negative patients and controls. Regional [18 F]PI-2620 binding was correlated with clinical and demographic data.

Results: Twenty-four percent (11 of 45) were β-amyloid-positive. Significantly elevated [18 F]PI-2620 distribution volume ratios were observed in both β-amyloid-positive and β-amyloid-negative patients versus controls in the dorsolateral prefrontal cortex and basal ganglia. Cortical [18 F]PI-2620 PET positivity was distinctly higher in β-amyloid-positive compared with β-amyloid-negative patients with pronounced involvement of the dorsolateral prefrontal cortex. Semiquantitative analysis of [18 F]PI-2620 PET revealed a sensitivity of 91% for β-amyloid-positive and of 65% for β-amyloid-negative cases, which is in excellent agreement with prior clinicopathological data. Regardless of β-amyloid status, hemispheric lateralization of [18 F]PI-2620 signal reflected contralateral predominance of clinical disease severity.

Conclusions: Our data indicate a value of [18 F]PI-2620 for evaluating corticobasal syndrome, providing quantitatively and regionally distinct signals in β-amyloid-positive as well as β-amyloid-negative corticobasal syndrome. In corticobasal syndrome, [18 F]PI-2620 may potentially serve for a differential diagnosis and for monitoring disease progression. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Keywords: Alzheimer's disease; PET; corticobasal syndrome; four-repeat tauopathies; tau.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alzheimer Disease* / diagnostic imaging
  • Amyloid beta-Peptides
  • Diagnosis, Differential
  • Humans
  • Positron-Emission Tomography
  • Syndrome

Substances

  • Amyloid beta-Peptides