The understanding of radiotracer's physiological biodistribution as well as the potential source of false-positive results is crucial for an accurate diagnostic interpretation of (18)F-fluorocholine PET/CT examination in patients with prostate cancer. We illustrate the results of whole-body (18)F-fluorocholine PET/CT in a 79-year-old man with biochemical suspicion of prostate adenocarcinoma relapse. PET/CT study showed a focally increased (18)F-fluorocholine uptake, characterizing an incidentally found adrenocortical adenoma. Finally, we draw oncologists' attention to the possible false-positive results of (18)F-fluorocholine PET related to benign and unsuspected adrenocortical lesions in patients with a history of prostate malignancy.