68Ga-PSMA-11 PET/MR Can Be False Positive in Normal Prostatic Tissue.

Prostate-specific membrane antigen (PSMA) is a transmembrane glycoprotein expressed in the cytosol of normal prostate tissue and highly overexpressed on the membrane of prostate cancer, therefore increasingly used to image prostate cancer. We report a case of a 65-year-old man with two focal PSMA-positive areas on a Ga-PSMA-11 PET/MR, one corresponding to a prostate carcinoma (Gleason score 4 + 3) and another region without any evidence of malignancy, but with corresponding high PSMA-expression on immunohistochemistry.