Ductal Carcinoma in Situ (DCIS)
DCIS: What to Know
Ductal carcinoma in situ (DCIS) is the earliest form of breast cancer. The abnormal cells stay inside the milk duct and haven’t spread into nearby tissue. You may hear it called stage 0, non-invasive breast cancer, or pre-cancer—all of these terms mean the same thing. Because DCIS hasn’t moved beyond the duct, it cannot spread to other parts of the body, and it is very treatable and curable.
Even though DCIS is confined, it can sometimes become invasive if the cells break through the duct wall. Since there’s no reliable way to know which cases will progress, almost all people diagnosed with DCIS are advised to receive treatment.
How is DCIS diagnosed?
Most people with DCIS don’t notice any symptoms at all. Occasionally, someone might see nipple discharge or feel a lump. DCIS is usually found during a routine screening mammogram. If something looks unusual, the radiologist may order a diagnostic mammogram or ultrasound. A biopsy provides the final diagnosis.
Is all DCIS the same?
No. DCIS varies from person to person. Your biopsy report will describe features that help determine whether your DCIS is low-risk or high-risk.
- When the cancer cells look more like normal cells, DCIS tends to grow slowly and is less likely to spread.
- When the cells look very different, it usually grows faster and has a higher chance of spreading.
These details help guide your treatment plan.
Timing of Treatment
You might be wondering if you need to start treatment right away. Not necessarily. DCIS doesn’t require immediate treatment because the abnormal cells are still contained within the duct. However, your medical team should advise you on the best timing for treatment.
Treatment Options
There are several effective options, and your care team will help you understand what fits best based on your biopsy results and the characteristics of your DCIS. All of these treatments have excellent survival rates.
Surgery
Lumpectomy or Mastectomy
A lumpectomy removes the area of DCIS plus a small rim of normal tissue (called a clear or negative margin) to make sure all of it is gone.
A mastectomy removes all breast tissue. Your surgeon may recommend this if there are multiple areas of DCIS or if the cosmetic outcome with lumpectomy is a concern. Reconstruction options can also be discussed.
Radiation Therapy
Radiation may be recommended after a lumpectomy to lower the chance of DCIS—or invasive breast cancer—coming back in the same breast.
Endocrine Therapy
DCIS is most commonly fueled by estrogen (called ER-positive DCIS). If that’s the case for you, medication in pill form may be recommended after surgery to reduce the risk of recurrence and to lower the chance of developing a new breast cancer in the other breast.
