Subacute Cerebral Infarct: An Unusual Cause of Radiotracer Uptake at 18 F-PSMA PET/CT.

Prostate-specific membrane antigen (PSMA) PET/CT has become an unparalleled modality in the diagnosis of primary and recurrent prostatic adenocarcinoma, often revealing sites of disease that were previously invisible on conventional imaging. In this 78-year-old man with suspected prostate cancer recurrence, PSMA PET/CT revealed focal radiotracer uptake in the brain, which would ordinarily raise suspicion for metastases, but was a false positive in the setting of a recent stroke. Increased PSMA uptake has been reported in subacute infarcts and primary and secondary brain tumors. Careful history and comparison with prior imaging are vital to avoid false-positive diagnosis in such patients.