Overview

Mammary duct ectasia (ek-TAY-zhuh) occurs when one or more milk ducts beneath your nipple widens. The duct walls may thicken, and the duct may fill with fluid. The milk duct may become blocked or clogged with a thick, sticky substance. The condition often causes no symptoms, but some women may have nipple discharge, breast tenderness or inflammation of the clogged duct (periductal mastitis).

Mammary duct ectasia most often occurs in women during perimenopause — around age 45 to 55 years — but it can happen after menopause, too. The condition often improves without treatment. If symptoms persist, you may need antibiotics or possibly surgery to remove the affected milk duct.

Though it's normal to worry about any changes in your breasts, mammary duct ectasia and periductal mastitis aren't risk factors for breast cancer.