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Mammary duct ectasia

Mammary duct ectasia (ek-TAY-zhuh) is a noncancerous breast condition that affects the tubes that carry milk, called the milk ducts. It happens when one or more milk ducts beneath your nipple widen, thicken and fill with fluid. This can cause the milk ducts to become blocked or clogged with a thick, sticky substance that often is yellow or green in color.

Mammary duct ectasia often has no symptoms. But some people may have:

Mammary duct ectasia most often happens during perimenopause, around age 45 to 55. But it also can happen after menopause. The condition often gets better without treatment. If symptoms don’t go away, you may need antibiotics or possibly surgery to remove the clogged milk duct.

Although changes in your breasts may seem concerning, mammary duct ectasia and periductal mastitis aren’t risk factors for breast cancer. It’s a good idea to talk with your healthcare professional about any changes in your breasts.

Mammary duct ectasia often doesn’t cause any symptoms. People with symptoms may have:

Sometimes, a blocked milk duct gets infected. This is called mastitis. Mastitis can cause breast tenderness, inflammation in the areola and fever.

Symptoms of mammary duct ectasia may get better on their own.

Make an appointment with your healthcare professional if you notice changes in your breasts that don’t go away or that worry you. Some things to watch for are a new breast lump, sudden nipple discharge, a change in skin color, skin swelling or irritation, or an inverted nipple.

Experts don’t know exactly what causes mammary duct ectasia. The condition may be related to changes in the breast tissue. Your breasts are made up of connective tissues that have tiny tubes inside called milk ducts that carry milk to your nipple. Mammary duct ectasia happens when a milk duct beneath the nipple widens, which often happens with age. The duct walls may thicken and fill with fluid, becoming blocked or clogged with a sticky substance. This can cause painful swelling, called inflammation.

Although the exact cause of mammary duct ectasia isn’t known, certain risk factors do exist. They include:

Usually, the complications of mammary duct ectasia aren’t serious, but they can be bothersome. They may include:

Mammary duct ectasia may be diagnosed based on information you give to your healthcare professional and the results of a physical exam. You also might need additional tests, such as:

Mammary duct ectasia doesn’t always require treatment. But if you have symptoms that bother you, treatment options may include:

To relieve pain caused by mammary duct ectasia, you might try these self-care measures:

If you notice a new lump in your breast or any other changes, you’ll likely see a member of your primary healthcare team first. Sometimes, based on a breast exam or the results of a mammogram or ultrasound, you may be referred to a breast health specialist.

What you can do

The first appointment focuses on your medical history and the symptoms you’re having, including how they’re related to your menstrual cycle. To prepare for this discussion with your healthcare professional:

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

What to expect from your doctor

Your healthcare professional may ask you several questions, such as:

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