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

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). ¹⁸F-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.