Affiliations: [a] Department of Neurology and Alzheimer Center, VU University Medical Center, Amsterdam, The Netherlands | [b] Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands | [c] Department of Pathology, VU University Medical Center, Amsterdam, The Netherlands | [d] Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA | [e] Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA | [f]
Geriatric Research Education and Clinical Center, Veterans Administration Pittsburgh Healthcare System, Pittsburgh, PA, USA | [g]
Institutes of Neurology and Healthcare Engineering, UCL, London, UK
Correspondence:
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Correspondence to: Colin Groot, MSc, VU University Medical Center, de Boelelaan 1117, Amsterdam, The Netherlands. Tel.: +31 204445240; Fax: +31 204448529; E-mail: [email protected].
Note: [1] These authors contributed equally to this work.
Abstract: This single case study examines selective Pittsburgh compound-B (PiB) binding to an intracerebral light-chain amyloidoma using a 90-minute dynamic [11C]PiB-PET scan and brain biopsy tissue. Parametric non-displaceable binding potential (BPND) images showed low specific binding in the amyloidoma (BPND = 0.23), while relative tracer delivery was adequate (R1 = 0.44). Histology of the tissue revealed strong coloring with Congo-red, thioflavin-S, and X-34, indicating presence of amyloid. However, immunological staining with 6F/3D revealed absence of amyloid-β and histofluorescence of 6-CN-PiB, a highly fluorescent derivative of PiB, was at background levels. Our results suggest that PiB does not detect the atypical amyloid pathology associated with an intracerebral light-chain amyloidoma. These findings are of interest to clinicians and researchers applying [11C]PiB-PET to detect atypical forms of amyloid pathology.
Keywords: Amyloid, case study, histology, positron emission tomography
