(warts of the breast ducts):

Tiny warts in the breast ducts are a common coincidental finding when looking at breast tissue under the microscope for other reasons.

They can occasionally cause problems the commonest of which is a blood stained nipple discharge. It is often necessary to remove the affected duct by doing a small operation to distinguish harmless papillomas from the more serious condition ductal carcinoma in situ.

The problem of multiple, larger and peripheral papillomas is contentious. Further research is being done to try to decide if these type of papillomas have a slightly increased risk of becoming cancer over a period of years. Some surgeons will recommend removal and others suggest follow up with regular mammograms.