Background: Evaluation of brain β-amyloid by positron emission tomography (PET) imaging can assist in the diagnosis of Alzheimer disease (AD) and other dementias.
Methods: Open-label, nonrandomized, multicenter, phase 3 study to validate the (18)F-labeled β-amyloid tracer florbetaben by comparing in vivo PET imaging with post-mortem histopathology.
Results: Brain images and tissue from 74 deceased subjects (of 216 trial participants) were analyzed. Forty-six of 47 neuritic β-amyloid-positive cases were read as PET positive, and 24 of 27 neuritic β-amyloid plaque-negative cases were read as PET negative (sensitivity 97.9% [95% confidence interval or CI 93.8-100%], specificity 88.9% [95% CI 77.0-100%]). In a subgroup, a regional tissue-scan matched analysis was performed. In areas known to strongly accumulate β-amyloid plaques, sensitivity and specificity were 82% to 90%, and 86% to 95%, respectively.
Conclusions: Florbetaben PET shows high sensitivity and specificity for the detection of histopathology-confirmed neuritic β-amyloid plaques and may thus be a valuable adjunct to clinical diagnosis, particularly for the exclusion of AD.
Trial registration: ClinicalTrials.govNCT01020838.
Keywords: Amyloid; Florbetaben; Histopathology; PET.
Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.