Gynecomastia is not uncommon in men older than 50 years of age and is characterized by glandular proliferation of breast tissue. Non-physiologic gynecomastia is mostly caused by a variety of external medical interventions. Medications that belong to classes of antiandrogens, antipsychotics, or antibiotics alter the levels of estrogen and testosterone and are commonly implicated in patients with gynecomastia. We are presenting a case of bilateral F-NaF uptake in the breast tissue of a 56-year-old man with known history of prostate cancer.