Unexpected detection of a meningioma on 18F-Fluorocholine PET/CT in a prostate cancer patient

Abstract

A 77-year-old man with a prior diagnosis of prostate adenocarcinoma, previously treated with radiotherapy and hormone therapy, presented with rising PSA levels suggestive of biochemical recurrence. While no evidence of metastatic prostate disease was detected, the PET/CT (positron emission tomography–computed tomography) scan incidentally revealed an area of abnormal radiotracer uptake in the left temporal lobe of the brain, unrelated to the patient’s known malignancy. The imaging characteristics raised the suspicion of a meningioma. A subsequent brain MRI confirmed the presence of an extra-axial lesion consistent with a meningioma. This unexpected finding highlights the additional diagnostic value of 18F-fluorocholine PET/CT beyond its primary role in prostate cancer imaging, particularly in detecting clinically significant incidental intracranial lesions. This case underscores the importance of careful and systematic interpretation of imaging studies during oncologic evaluations, even in regions outside the primary area of concern.