Detection of benign granular cell tumor of the breast via ¹⁸F-PSMA-PET/CT in a patient with very high-risk prostate cancer: A case report

Incidental extra-prostatic prostate-specific membrane antigen (PSMA) uptake on initial staging positron emission tomography/computed tomography (PET/CT) scans poses diagnostic challenges, as it can be associated with various benign and malignant lesions. We present the case of a 68-year-old man with very high-risk prostate cancer who was incidentally discovered to have a benign granular cell tumor in the breast initially detected on PSMA-PET/CT. Imaging studies and biopsy were pivotal in the diagnosis, as the tumor’s appearance was concerning for breast carcinoma. Recognizing extra-prostatic PSMA uptake in the breast, particularly in patients with prostate cancer, is crucial for guiding appropriate management, accurately interpreting subsequent imaging findings, and assessing radiologic-pathologic correlation.