Why does duct ectasia cause nipple discharge?

Milk ducts are small channels behind the nipple. With duct ectasia, a duct becomes wider and its lining may become irritated. Secretions can become thicker, mix with shed cells, and remain in the duct before reaching the nipple. This may produce discharge that is green, yellow, brown, white, or dark, and it can come from one or more openings. The discharge may appear without squeezing, although pressure can also bring it out.

Nipple Discharge is a common presentation of Duct Ectasia. Discharge alone cannot identify its cause, because hormonal changes, medicines, infection, and other breast conditions can also be involved.

Arrange a clinical assessment if the discharge is new, persistent, or comes from one breast. Note its colour, whether it appears on its own, which nipple opening is involved, and whether you have a lump, tenderness, redness, or fever. Avoid repeated squeezing, which can keep the duct stimulated and make the discharge continue. A clinician may examine the breast and decide whether imaging or another test is appropriate.

Seek prompt medical care for bloody or clear discharge, a new lump, nipple inversion, skin dimpling, marked redness, warmth, swelling, fever, or worsening pain. These findings need assessment even when duct ectasia is possible. Seek urgent help if you feel very unwell or develop rapidly increasing breast swelling.

Could the discharge pattern fit duct ectasia, and what other causes should be considered? Do I need breast imaging? Which changes should lead me to return sooner?