In gynecomastia, what is the typical sonographic appearance?

• A. Hypoechoic to hyperechoic tissue beneath the areola representing glandular and fibrous tissue
• B. Simple cyst in the breast
• C. Hyperechoic fatty mass
• D. Ductal dilation without tissue proliferation

Answer: (A)

Gynecomastia is defined by proliferation of glandular and fibrous tissue directly beneath the areola. On ultrasound, this subareolar tissue appears as a band or small triangular/fan-shaped area behind the nipple-areolar complex, and its echogenicity can vary from hypo- to hyper-echogenic compared with surrounding fat, depending on the amount of fibrous versus glandular tissue present. This variability in appearance reflects the tissue makeup rather than fluid or fat alone. It is not a simple cyst (which would be an anechoic fluid-filled structure), not a fatty mass (which would be predominantly echogenic fat without a glandular component), and not just ductal dilation without tissue proliferation.