Breast Cancer Screening: Mammogram Showing DCIS (Ductal Carcinoma in Situ)

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Ductal Carcinoma in Situ: Overview

Cancer is often compartmentalized by the areas of the body it affects. In the case of breast cancer, this disease affects one or both of the breasts; there are varying types of breast cancers as well, including DCIS.

By definition, DCIS is a common noninvasive form of breast cancer, although some argue that it is “pre-cancer” versus cancer. Its growth is confined within the breast’s milk duct, or ducts. Being that it is in situ, or “in position”, it generally does not raid other parts of the breast; however, DCIS can become invasive if the individual does not undergo any sort of treatment, especially if the subtype is aggressive, or “high-grade”.

Breast Cancer Screening: Diagnosing Ductal Carcinoma

In recent years, it has appeared that DCIS was surging; however, much of this has been attributed to an increased amount of mammography screenings. In the past, prior to widespread mammography use, DCIS generally remained undiagnosed until its mass could be felt or atypical nipple discharge was discovered. In turn, such a late diagnosis led to a less favorable prognosis.

Nowadays, with more women undergoing routine screenings, a mammogram showing DCIS is quite significant. Mammograms are generally the first line of defense when it comes to ruling out any sort of breast cancer, including DCIS. If flecks of calcium (microcalcifications) are discovered on mammogram imaging, a biopsy is conducted to confirm or rule out the presence of DCIS.

Three known biopsies used to provide further analysis include:

1. Core needle biopsy –

Up to fifteen tissue samples, individually the size of a rice grain, are removed with a hollow needle for analysis.

2. Stereotactic biopsy –

Locating the area(s) of suspicion through the assistance of stereo images, a hollow needle is inserted into the patient’s tissue to retrieve samples.

3. Surgical biopsy –

If either of the above biopsies have indicated DCIS, a larger mass of breast tissue is removed for analysis through surgical removal.

Breast MRI vs. Mammogram

Of note, mammograms do not have a reliable history in determining the patient’s DCIS subtype; therefore, health care providers have found it difficult in determining the correct treatment for their patients.

Recent anecdotal evidence suggests that magnetic resonance imaging (MRI) is much more effective in diagnosing DCIS, particularly its high-grade subtype, reports Megan Rauscher in her article, “MRI Best at Spotting Ductal Carcinoma in Situ”, last updated June 4, 2007.[1] Given this information, treatment plans can be set accordingly while saving women from unnecessary procedures, such as mastectomies. MRIs will not necessarily replace mammograms; however, the American Cancer Society recommends the use of MRIs for women considered at high-risk for developing breast cancer.[2]

Disclaimer: The preceding article is presented for educational purposes only and should not replace the advice of a licensed health care professional.


Rauscher, Megan. “MRI Best at Spotting Ductal Carcinoma in Situ”, Reuter’s Health,[1] “MRI Best at Spotting Ductal Carcinoma in Situ”,[2]

Mayo Clinic. “Ductal Carcinoma in Situ (DCIS)”,

Dana-Farber Cancer Institute. “Questions and Answers About DCIS Breast Cancer”,

Dana-Farber Cancer Institute. “DCIS: A Breast Cancer Dilemma”,

Patient Resources

Dana-Farber Cancer Institute. “Cancer Information”,,