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Mammary duct ectasia

Mammary duct ectasia is a benign condition where the walls of a breast milk duct become thicker and wider than normal. The duct becomes blocked and fluid builds up behind the blockage. It may occur in one or both breasts.

Mammary duct ectasia is more common in women between the ages of 40 and 50. It does not increase a woman’s risk of developing breast cancer.

Signs and symptoms

The signs and symptoms of mammary duct ectasia may include:

  • green or black coloured nipple discharge (may be thick and sticky)
  • pain or tenderness of the nipple and surrounding breast tissue
  • redness and swelling of the nipple
  • a lump in the area below the nipple (caused by scar tissue)
  • a nipple starts to point inwards (invert)
  • infection


If the signs and symptoms of mammary duct ectasia are present, or if the doctor suspects mammary duct ectasia, tests will be done to make a diagnosis. Tests may include:


Mammary duct ectasia usually goes away on its own without treatment. The doctor may suggest supportive care measures that treat the symptoms of pain and discomfort:

  • warm cloths applied to the nipple area
  • over-the-counter pain medication
  • wearing bra pads to absorb the nipple discharge
  • wearing a supportive bra

If mammary duct ectasia does not improve on its own, treatment options may include:

  • antibiotics to treat infection
  • surgery to remove the affected milk duct


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