False Positive Uptake in Bilateral Gynecomastia on 68Ga-PSMA PET/CT Scan.

A 66-year-old man on hormonal therapy with prostate cancer was referred for Ga-68-PSMA PET/CT scan for biochemical recurrence. Ga-68-PSMA PET/CT scan detected moderate heterogeneous tracer concentration in bilateral breast parenchyma, in addition to the abnormal tracer concentration in enlarged prostate gland, right external iliac lymph node, and sclerotic lesion in L4 vertebra. On clinical examination, he was found to have bilateral gynecomastia. Abnormal concentration of Ga-68-PSMA in breast cancer is now well known, and in this context, it is important to know that tracer localization can occur in gynecomastia as well, as evidenced in this case.