Ductal carcinoma in situ (DCIS) involves abnormal cells that form in a milk duct in your breast. Because these abnormal cells haven’t spread beyond the milk duct to the surrounding tissue, it has a high cure rate.
DCIS is considered a stage 0 or preinvasive cancer. In other words, it’s a precursor to breast cancer.
In this article we’ll take a closer look at DCIS as well as the known risk factors, treatment options, and the outlook.
Your breasts are made of three different types of tissue:
- lobes (which are made up of smaller sacs called lobules, which make milk)
- ducts (which transport milk to your nipple)
- fatty or fibrous connective tissue
DCIS happens when a group of abnormal cells starts growing inside the lining of a milk duct. Because these cancerous cells haven’t spread beyond the duct to other breast tissue, it’s known as a preinvasive or noninvasive cancer.
Sometimes, especially if these abnormal cells aren’t treated early on, they can become an invasive form of breast cancer. Invasive breast cancer has the capacity to spread to other parts of your body. When this happens, the breast cancer is said to have metastasized.
According to the American Cancer Society, DCIS accounts for about 16 percent of all breast cancer diagnoses in the United States.
You can’t usually see or feel the abnormal cells in your milk duct. As a result, you may not have any symptoms. In fact, in the vast majority of cases, DCIS is detected during a breast cancer screening using a mammogram.
The abnormal cells typically show up on a mammogram as clusters of bright white flecks (known as microcalcifications) with irregular shapes.
In some cases, DCIS may cause symptoms such as:
- discharge coming from a nipple that isn’t milk
- a small lump
Most breast symptoms or changes aren’t caused by cancer, but tests are often needed to rule out the possibility of abnormal breast cells.
Exactly what causes DCIS isn’t known. Still, research has shed light on some of the possible factors that may increase your risk of developing a breast cancer diagnosis.
It’s important to know that your risk of developing breast cancer isn’t usually dependent on a single factor. You may have several risk factors, but that doesn’t necessarily mean you’ll get breast cancer.
However, understanding your risk factors can help you make better decisions about your health and healthcare.
The following factors may contribute to a higher risk of breast cancer:
Some risk factors — your age, for example — are things beyond your control. But some aspects of your lifestyle can affect your overall health and your risk of developing breast cancer.
Most of the time, DCIS is diagnosed through a routine breast cancer screening.
If your doctor thinks you might have DCIS, you’ll probably need further tests to confirm the diagnosis. These tests may include:
The report that comes back from the pathologists in the lab may contain some unfamiliar terms, like the ones described below:
A biopsy will also be able to determine the hormone receptor status of the DCIS cells. Many times, DCIS will have receptors that respond to the hormones estrogen or progesterone.
If these hormone receptors are present, it can help your doctor decide whether to offer you anti-estrogen medication to reduce the risk of recurrence.
Because DCIS involves the diagnosis of abnormal cells at a very early stage, treatments are usually highly effective.
Also, since the abnormal cells are only found in your breast duct, chemotherapy is never needed for DCIS.
Let’s take a closer look at some treatment options you and your healthcare team may decide to use, based on your specific diagnosis and situation.
Sometimes called breast-conserving surgery, a lumpectomy removes the tissue that contains the abnormal cells along with some surrounding tissues.
A lumpectomy preserves as much of your breast as possible. It’s often followed with radiation therapy which helps reduce the risk of the DCIScoming back.
This type of surgery removes as much of the breast tissue as possible.
If DCIS is present in more than one place in your breast, or if there is a large area of DCIS, mastectomy may be the best option for your treatment.
Radiation therapy is often used after a lumpectomy to reduce the risk of the DCISreturning.
Radiation therapy uses high energy beams to damage the DNA of cancer cells. This helps to destroy the abnormal cells.
Radiation therapy is a localized type of treatment, which means it only targets the specific area that’s being radiated. This helps limit the damage to healthy cells.
Hormone therapy is an option if your cancer cells are hormone-receptor-positive. This means the cancer cells grow in response to estrogen or progesterone.
Hormone therapy can be added to your treatment plan after surgery to lower your risk of DCIS recurring in the future.
Two commonly prescribed hormonal therapies include:
The survival rate for people diagnosed with DCIS is very good.
A 2015 study that reviewed data involving 100,000 women over a 20-year span found that
An important note
It’s important to note that the stress of enduring racism, discrimination, and racist systems may play a part in developing the disease beyond genetic factors.
After your DCIS treatment, it’s important to follow up with your healthcare team regularly to get regular screenings to make sure the cancer cells don’t return.
Ductal carcinoma in situ (DCIS) is a preinvasive breast cancer that has a very high cure rate. DCIS generally doesn’t have any symptoms and is most often detected during a mammogram.
Depending on the size and location of the affected cells, treatment of DCIS may involve a lumpectomy or mastectomy. Treatment could also include radiation and hormone therapy to prevent the cancer cells from returning.
Overall, DCIS has a very good outlook.