Ductal carcinoma in situ (DCIS) is a non-invasive breast cancer.
In DCIS, the abnormal cells are contained in the milk ducts (canals that carry milk from the lobules to the nipple openings during breastfeeding). It is called “in situ” (which means "in place") because the cells have not left the milk ducts to invade nearby breast tissue.
DCIS is also called intraductal (within the milk ducts) carcinoma. You may also hear the terms “pre-invasive” or “pre-cancerous” to describe DCIS.
DCIS is non-invasive, but without treatment, the abnormal cells could turn into invasive cancer over time. At this time, health care providers cannot predict which cases of DCIS will progress to invasive breast cancer and which will not. So, almost every case of DCIS is treated.
Treatment for ductal carcinoma in situ (DCIS) usually involves surgery with or without radiation therapy. After surgery and radiation therapy, some women may take tamoxifen, a hormone therapy.
With treatment, prognosis is usually excellent.
Learn more about treatment for DCIS.
Learn about the risk of invasive breast cancer after treatment for DCIS.
Read our perspective on DCIS (March 2013).*
*Please note, the information provided within Komen Perspectives articles is only current as of the date of posting. Therefore, some information may be out of date at this time.
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