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Mammary duct ectasia

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.

Mammary duct ectasia often doesn’t cause any signs or symptoms, but some people experience:

A bacterial infection called mastitis also may develop in the affected milk duct, causing breast tenderness, inflammation in the area around the nipple (areola) and fever.

Signs and symptoms of mammary duct ectasia may improve on their own.

Make an appointment with your doctor if you notice changes in your breasts — such as a new breast lump, spontaneous nipple discharge, skin redness or inflammation, or an inverted nipple — that are persistent or that worry you.

Your breasts are made up of connective tissues that include a system of tiny passages that carry milk to the nipples (milk ducts). Mammary duct ectasia occurs when a milk duct beneath the nipple widens. The duct walls may thicken and fill with fluid, becoming blocked or clogged with a sticky substance. Inflammation may result.

Experts don’t know exactly what causes mammary duct ectasia. Some speculate the cause to be associated with:

Complications of mammary duct ectasia are usually minor and often more bothersome than serious. These may include:

Based on information you provide to your doctor and the results of a physical exam, you might need additional tests, including:

Mammary duct ectasia doesn’t always require treatment. If your symptoms are bothersome, however, treatment options may include:

To relieve discomfort associated with mammary duct ectasia, you might try these self-care measures:

For evaluation of a new breast lump or changes in your breast, you’re likely to start by seeing your primary care doctor. In some cases, based on a clinical breast exam or findings on the mammogram or ultrasound, you may be referred to a breast health specialist.

What you can do

The initial evaluation focuses on your medical history and the signs and symptoms you’re experiencing, including how they’re related to your menstrual cycle. To prepare for this discussion with your doctor:

For mammary duct ectasia, here are some questions you might ask your doctor:

What to expect from your doctor

Your doctor may ask you a number of questions, such as:

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