Abnormal 18F-FDG uptakes in the prostate due to two different conditions of urine reflux: a mimicker of prostate cancer.

A 69-year-old man with lung cancer underwent 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT for staging. FDG PET/CT showed high uptakes in the prostate gland with calcification, and magnetic resonance imaging was recommended to check the prostatic malignancy. T2-weighted images revealed midline cystic lesion at the base to midgland level and cystic lesion in right apical peripheral zone. We suspected urine reflux conditions. Voiding cystourethrography demonstrated those cystic lesions were communicating with the urethra. Therefore these lesions were diagnosed as the prostatic utricle cyst and the dilated prostatic duct in peripheral zone. We conclude that the urine reflux condition should be recognized as a prostate benign lesion with FDG accumulation.