Why does Paget disease of the breast cause nipple discharge?

Paget disease begins in the nipple area and may involve the ducts just behind the nipple. Changes to those cells can irritate the nipple, while duct involvement can allow fluid to reach the nipple opening. The discharge may occur with crusting, scaling, redness, itching, burning, a flattened or turned-in nipple, or a lump deeper in the breast.

Nipple Discharge is a common presentation of Paget Disease of the Breast. However, nipple discharge has many possible explanations, including hormonal changes, blocked or widened ducts, medicines, infection, and other breast conditions. Its colour, whether it comes from one or both nipples, whether it appears without squeezing, and whether there are skin changes all help guide assessment.

Arrange a medical assessment for new discharge, especially if it comes from one breast, appears without touching the nipple, is bloody or clear, or occurs with a persistent nipple or skin change. Do not repeatedly squeeze the nipple to check for fluid, because stimulation can keep discharge going. Note when it happens, its colour and texture, and any pain, rash, crusting, lump, or change in nipple shape.

A clinician may examine the breast and ask about medicines, pregnancy or breastfeeding, menstrual changes, and family history. Depending on the findings, they may recommend breast imaging or a small tissue sample to identify the cause.

Seek prompt advice if discharge is bloody, occurs without squeezing, or is paired with a new lump, one-sided nipple change, persistent crusting, or skin thickening. Seek urgent care for a rapidly worsening red, hot, painful breast with fever, or if you feel acutely unwell, because infection can need prompt treatment. A discharge change cannot be interpreted safely from appearance alone.

Ask: Could the discharge be coming from the nipple skin, a milk duct, an infection, or a medicine? Do the nipple and areola need a closer examination? What imaging or tissue testing is appropriate for my findings? What changes should I report while I am waiting for assessment?