Multifocal Meningiomas Mimicking Metastasis on 18F-Fluciclovine PET/CT

Abstract

A 65-year-old male patient with a past medical history of prostate adenocarcinoma presented with biochemical recurrence (prostate-specific antigen level of 5.91 mg/L). 18 F-FACBC PET/CT was acquired to evaluate the disease recurrence and metastasis. Multifocal areas of tracer uptake localized to the dural surface of frontal convexities and cavernous sinuses were seen. Subsequent MRI confirmed lesions to be consistent with multifocal meningiomas. Focal intracranial 18F-fluciclovine radiotracer uptake especially at the skull base may present with a diagnostic challenge, and it may be difficult to differentiate between bone metastasis and meningiomas. Keywords 18F-fluciclovine • 18 F-FACBC • Meningioma • PET/CT • Prostate cancer 18 F-FACBC PET/CT is a novel technique that has gained increasing popularity for evaluating recurrent prostatic adenocarcinoma in patients with an elevated prostate-specific antigen (PSA) who have received prior cancer therapy [1,2]. 18 F-FACBC used in this imaging modality is a synthetic radiolabeled amino acid that takes advantage of the prostatic cancer cell upregulation of transmembrane amino acid transport due to increased amino acid metabolism for energy production and protein synthesis [3,4]. These amino acid transporters include LAT1 (l-type amino acid transporter 1) and ASCT2 (alanine-serine-cysteine transporter 2) which * Amro Saad Aldine