Duct ectasia, also known as mammary duct ectasia, is a benign (non-cancerous) breast condition that occurs when a milk duct in the breast widens and its walls thicken. This can cause the duct to become blocked and lead to fluid build-up. It’s more common in women who are getting close to menopause. But it can happen at other ages, too.
Often, this condition causes no symptoms and is found when a biopsy (removal of small pieces of breast tissue to be checked with a microscope) is done for another breast problem.
Less often, duct ectasia may cause a nipple discharge, which is often sticky and thick. The nipple and nearby breast tissue may be tender and red, and the nipple may be pulled inward. Sometimes scar tissue around the abnormal duct causes a hard lump that may be confused with cancer. A mammogram and/or breast ultrasound may be done to learn more about the changed part of your breast.
Duct ectasia does not increase your risk for breast cancer.
Duct ectasia that is causing symptoms sometimes gets better without treatment. Warm compresses and antibiotics may be used in some cases. If the symptoms don't go away, the abnormal duct might need to be surgically removed.
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Last Revised: January 25, 2022
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