(IN-truh-DUK-tul brest KAR-sih-NOH-muh)

A condition in which abnormal cells are found in the lining of a breast duct. The abnormal cells have not spread outside the duct to other tissues in the breast. In some cases, intraductal breast carcinoma may become invasive breast cancer and spread to other tissues. At this time, there is no way to know which abnormal cells could become invasive. Also called DCIS and ductal carcinoma in situ.

Figure

Ductal carcinoma in situ (DCIS). Abnormal cells are found in the lining of a breast duct.