Ductal Carcinoma in Situ

What is DCIS?

Ductal carcinoma in situ (DCIS) is a type of breast cancer found in the milk ducts. It is considered non-invasive, meaning it has not spread to nearby breast tissue outside of the milk ducts. It’s highly treatable, and people have excellent outcomes when it’s detected early.

Early detection is important because DCIS could develop into invasive breast cancer if it isn’t treated. By catching DCIS early, health care providers can treat it and prevent it from spreading. Routine mammograms can uncover DCIS so it can be treated in this early stage. 

DCIS accounts for about 20% of all breast cancer diagnoses in the United States. 

Causes and risk factors of DCIS

DCIS happens when cells in your milk ducts grow out of control, but experts don’t know why this happens. These factors may raise your risk:

• Being over the age of 50
• A family or personal history of breast cancer
• Having genetic mutations, such as BRCA1 or BRCA2
• Starting your period before age 12
• Having a baby after age 30 or never being pregnant or breastfeeding
• Having a previous breast cancer diagnosis
• Taking hormone replacement therapy for menopause symptoms
• Having dense breast tissue 
• Having previous radiation therapy directed at your breasts or chest before age 30
• Drinking alcohol
• Obesity

Signs and symptoms of DCIS

Most people with DCIS don’t have any symptoms or signs of a problem and feel normal. That’s why routine breast cancer screenings are important.

In rare cases, you may notice DCIS symptoms such as:

• A breast lump
• Clear or bloody nipple discharge
• Changes in the breast or nipple such as dimpling or an inverted nipple

If you notice any changes in your breasts, it’s important to talk to your health care provider. Most changes are not related to cancer, but you should still see a professional to have them evaluated.

How DCIS is diagnosed

Screening mammograms are the main method of diagnosing DCIS. Mammograms can spot small calcium deposits, called microcalcifications, that may be a sign of DCIS. If the mammogram results show something suspicious, your doctor may recommend additional imaging tests like:

• Diagnostic mammogram, to examine the area more closely.
• Ultrasound, which uses sound waves to create images of breast tissue and can evaluate lumps or other abnormalities.
• MRI (magnetic resonance imaging), which uses magnets and radio waves to create detailed images. MRI is often used if you are at higher risk of breast cancer or have dense breast tissue.

If imaging tests show signs that could be DCIS, a biopsy is usually the next step. During biopsies, radiologists use a small needle to remove samples of tissue from the suspicious area in the breast. These tissue samples are then sent to a lab for analysis by pathologists. The pathologist examines the tissue under a microscope to confirm whether DCIS is present. DCIS can be any size and can be found in one or more milk ducts.

Staging and grading DCIS

DCIS is classified as stage 0 breast cancer, because the abnormal cells have not spread to surrounding breast tissue or other parts of the body. 

Grading is different from staging. It refers to how abnormal the cells look under a microscope:

• Low-grade DCIS: Cancer cells are mildly abnormal. The risk of these cancer cells becoming invasive cancer is lower than higher-grade DCIS.
• Intermediate-grade DCIS: Cancer cells are moderately abnormal and grow faster than low-grade DCIS cells.
• High-grade DCIS: Cancer cells look very abnormal and grow more quickly. The risk of invasive cancer is higher than low-grade and intermediate-grade DCIS.

The grade affects your treatment recommendations. With high-grade DCIS, you many need more aggressive treatment.

DCIS treatment options 

Treatment for DCIS is important. If untreated, DCIS may become invasive cancer and more difficult to treat. DCIS breast cancer treatment usually starts with surgery:

• Lumpectomy: A lumpectomy removes the DCIS and a small amount of healthy tissue around it. It preserves most of the breast. After surgery, most people can return to normal activities within a few weeks.
• Mastectomy: If DCIS affects a large area of the breast, surgery to remove the entire breast may be an option. There are different types of mastectomies, including total mastectomy, skin-sparing mastectomy and nipple-sparing mastectomy. Breast reconstruction surgery options may be available, depending on treatment plans.

After surgery, you may need treatment to lower the risk of cancer returning:

• Hormone therapy: If DCIS is hormone-receptor positive, hormone therapy to lower or block estrogen levels may decrease your risk of developing breast cancer in the future. 
• Radiation therapy: High-energy rays can target cancer cells that may remain in the breast after a lumpectomy. Treatment is usually given over several weeks to lower the risk of cancer coming back. Most people need radiation therapy after lumpectomy.

Living with and managing DCIS

When DCIS is detected and treated early, the prognosis is excellent. After treatment, care focuses on preventing DCIS from returning and possibly becoming invasive breast cancer in the future.

Regular follow-up care is important. Your health care team will schedule mammograms and physical breast exams to check your breast health and spot any changes early. Most people have follow-up appointments every six to 12 months at first and less often over time. Be sure to tell your provider about any symptoms, such as skin changes, lumps or nipple discharge.

Coping with a cancer diagnosis may affect your mental health. Try stress management strategies like exercise, meditation, yoga or deep breathing. If you’re struggling with your emotions at any point during or after diagnosis or treatment, reach out to a counselor or therapist or consider joining an in-person or online support group.

Reducing your risk

You can’t completely prevent DCIS, but you can take these steps to reduce your risk of developing breast cancer and catch it early:

• Maintain a healthy weight, since obesity has been linked to an increased risk of breast cancer. Eat healthy meals rich in whole grains, vegetables, fruits, nuts and seeds.
• Limit alcohol. Drinking alcohol in any amount can increase the risk of breast cancer. 
• Stay physically active to lower your overall cancer risk and improve your health.
• Breastfeed, if possible. Breastfeeding may reduce your risk of breast cancer.
• If you have a family history of breast cancer, consider genetic counseling to understand your risk. Genetic testing can help identify genetic mutations that may increase your odds of breast cancer.
• Talk with your health care provider about when you should begin regular breast cancer screening and how often you should be tested. At age 40, women at average risk should start having screening mammograms once a year. Women at higher-than-average risk may be eligible for breast cancer screening at a younger age or may need additional tests.
• If you believe that you might have an elevated risk of developing breast cancer, consider a consultation at the High-Risk Breast Cancer Clinic to discuss intensive screening options and strategies to reduce your cancer risk.

Why choose Banner MD Anderson for DCIS care?

At Banner MD Anderson Cancer Center, our oncologists, radiologists, surgeons and breast health experts work together to provide care for people with DCIS and other breast conditions. Our team supports you every step of the way, so you feel informed and empowered as you consider your treatment options.

We also offer counseling, nutrition guidance and access to support groups for you and your loved ones. Treating cancer goes beyond medical care - it’s about caring for your overall well-being. 

Request an appointment