Ductal Carcinoma In Situ (DCIS)

About 1 in 5 new breast cancers will be DCIS or ductal carcinoma in situ. Nearly all women with this early stage of breast cancer can be cured.

Ductal carcinoma in situ(DCIS), is also called intraductal carcinoma and Stage 0 breast cancer. DCIS is a non-invasive or pre-invasive breast cancer. This means the cells that line the ducts have changed to cancer cells but they have not spread through the walls of the ducts into the nearby breast tissue.

Because DCIS hasn’t spread into the breast tissue around it, it can’t spread (metastasize) beyond the breast to other parts of the body.

DCIS is considered a pre-cancer because sometimes it can become an invasive cancer. This means that over time, DCIS may spread out of the duct into nearby tissue, and could metastasize (spread). Right now, though, there’s no good way to know for sure which will become invasive cancer and which ones won’t. So almost all women with DCIS will be treated.

illustration showing details of ductal carcinoma in situ including lobule, duct, normal duct and abnormal cells in duct

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Corben AD and Brogi E. Chapter 21: Ductal Carcinoma In Situ and Other Intraductal Lesions: Pathology, Immunohistochemistry, and Molecular Alterations. In: Harris JR, Lippman ME, Morrow M, Osborne CK, eds. Diseases of the Breast. 5th ed. Philadelphia, Pa: Lippincott-Williams & Wilkins; 2014.

Van Zee KJ, White J,  Morrow M, and Harris JR. Chapter 23: Ductal Carcinoma In Situ and Microinvasive Carcinoma. In: Harris JR, Lippman ME, Morrow M, Osborne CK, eds. Diseases of the Breast. 5th ed. Philadelphia, Pa: Lippincott-Williams & Wilkins; 2014.

Last Medical Review: June 1, 2016 Last Revised: August 18, 2016

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