Urinary Reflux Into the Prostate Gland and Seminal Vesicles: A Potential Pitfall in 18F-FDG and 68Ga-PSMA PET/CT.

: A 64-year-old man with lung cancer underwent F-FDG PET/CT for restaging, which demonstrated intense F-FDG uptake in the right lobe of prostate gland and seminal vesicles, indicating a potential prostate cancer. In Ga-PSMA PET/CT, intense uptake in the right lobe of prostate gland and seminal vesicles was also observed but decreased in postmictional delayed images. Magnetic resonance imaging showed high signal intensity of urine in the same areas of uptakes. F-FDG and Ga-PSMA PET/CT findings in the prostate gland and seminal vesicles were considered to be a result of urinary reflux possibly because of the patient's previous transurethral resection.