Incidental Uptake in a Subacute Stroke on 18F-Piflufolastat PSMA PET/CT

Abstract

Prostate-specific membrane antigen (PSMA) PET/CT has proven to be effective in the evaluation of prostate cancer and has become increasingly used clinically as multiple radiopharmaceuticals have become commercially available. With increasing use, incidental uptake from a variety of nononcologic processes will be encountered and considered interpretive pitfalls. We outline a case of a 71-year-old man who underwent imaging with PSMA PET/CT, which demonstrated uptake in the left parietal-temporal junction that was shown to be a subacute stroke. This case demonstrates a reported cause of uptake on PSMA PET for which the underlying mechanism is not yet well understood.

Subacute Cerebral Infarct

“…Correct diagnosis of subacute cerebral infarct was confirmed by 2-week prior history of stroke and compatible MRI. Increased PSMA uptake has been reported in subacute cerebral infarcts, 2–4 primary brain tumors such as gliomas and meningiomas and brain metastases of nonprostatic origin, 5–7 and intracranial hemorrhage 8,9 . A possible reason is increased endothelial PSMA expression in neovasculature, which would explain the positive uptake on the PSMA PET/CT in this patient, 2 weeks after the onset of neurological symptoms.…”