Ductal carcinoma in situ (DCIS)

Ductal carcinoma in situ (DCIS) is a non-invasive type of breast cancer that occurs when abnormal cells are found solely within the milk ducts. The words “in situ” means that the cells have remained in place and have not spread outside of the ducts into surrounding breast tissue. It is estimated that 50,000 women will be diagnosed with DCIS each year.

DCIS is considered to be a non-invasive breast cancer, which is why it’s called a Stage 0 cancer. It actually can be found in either women or men, although it is rare for men, where the cancer forms in breast ducts and is called lobular carcinoma.

Signs and symptoms

DCIS typically is found during a routine mammogram and often has few, if any, early symptoms. In fact, more than 80% of cases are found during an annual mammogram. Sometimes, though, there can be

  • A noticeable lump
  • An unusual or bloody discharge from the nipple
  • Thick, wrinkled skin on the breast
  • Breast pain

The number of women diagnosed with DCIS is on the rise, primarily because more women are getting regular mammograms. Depending upon family history of breast or other cancers, routine mammograms are recommended beginning at age 40.

How is it diagnosed?

If a suspicious area is found on a routine mammogram, the radiologist will recommend an additional mammogram—called a diagnostic mammogram—to take a closer look. A breast tissue biopsy also may be scheduled. 

Treatment options

Treatment options depend upon how large an area has DCIS or if there are multiple areas. Recommendations also will take into account your family medical history of cancer.


This is surgery to remove the tissue where DCIS is detected, as well as some surrounding healthy tissue. Lumpectomy without any additional treatment is designed for patients who have a small, clearly defined area of DCIS.

Lumpectomy plus radiation therapy

This option, which follows surgery with a determined number of external beam radiation treatments, is the most common treatment plan for DCIS. The radiation therapy minimizes the risk of the cancer returning or spreading.

Lumpectomy plus tamoxifen

In some cases, cancer doctors will recommend a lumpectomy followed by the drug tamoxifen. Tamoxifen blocks the hormone estrogen, which, in some cases, can promote tumor growth and the spreading of cancer cells. Your doctor will tell you if hormones are impacting your specific cancer.


A mastectomy, where the surgeon removes the breast tissue, skin, areola and nipple, is recommended if DCIS is found in a large portion of the breast, or if there are multiple areas of abnormal cells. It’s also recommended if the area of DCIS does not have clearly defined margins (meaning abnormal cells are near the edges of the area and increase the risk of spreading beyond the ducts).

Nipple-sparing mastectomy

At University of Iowa Health Care, breast and plastic surgeons also offer nipple-sparing mastectomy. This procedure allows you to keep some of your breast skin, including the nipple and areola, after mastectomy.

Our expertise

At University of Iowa Health Care, we have long-standing expertise in breast cancer diagnosis and treatment.

  • We are a Breast Imaging Center of Excellence designated by the American College of Radiology
  • We offer 3D mammography (tomosynthesis) to better identify early breast cancers
  • We meet or exceed breast cancer quality measures set by the Commission on Cancer (CoC) of the American College of Surgeons.
  • We have a multidisciplinary team approach to the treatment of breast cancer. Surgical. medical and radiation oncologists work together with pathologists, plastic and reconstructive surgeons, nurses, genetics counselors and pharmacists to develop an individualized treatment plan that is tailored to you and your specific type of breast cancer.

National DCIS study

Physicians in the Holden Cancer Center at the University of Iowa are participants in the Comparison of Operative to Monitoring and Endocrine Therapy (COMET) Study to better determine how to treat low-risk DCIS.

Previous studies have found that up to 80% of DCIS cases may never develop into invasive breast cancer. The COMET study hopes to determine if active surveillance, or more frequent follow-up and mammograms, will help more women avoid surgery and the long-term emotional and physical side effects that may occur.

Learn more about the COMET study. 

Last reviewed: 
March 2018

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