In 2019, more than 300,000 women received a breast cancer diagnosis. About 50,000 of these women learned that they had the earliest form of breast cancer, Ductal Carcinoma in Situ, DCIS for short. DCIS affects women of every age, but it can be confusing to understand and treat. Bright Pink called in expert Dr. Swati Kulkarni to tell us more about this type of breast cancer, from prevention, to diagnosis to treatment. You can also check out her Facebook Live conversation here.
What is DCIS* -Do I have cancer?
Ductal Carcinoma in Situ (DCIS) is made up of abnormal cells that are enclosed in the milk ducts of the breast. DCIS cells grow faster than normal cells, but they lack one of the key hallmarks of cancer- the ability to invade other tissues.
Over time, however, DCIS can turn into invasive cancer, leaving the milk ducts and spreading to other tissues. That is why it is important to treat DCIS – to prevent a future case of invasive breast cancer.
What are the risk factors for DCIS? How can I reduce my risk?
DCIS or invasive breast cancer may run in your family. Other women may develop DCIS because of their environment, and for some women, we do not know why they developed DCIS.
Maintaining a healthy weight and limiting the amount of alcohol you drink are two things that you can do to help reduce your risk of developing DCIS.
(Want to learn more about reducing your breast cancer risk? Check out Bright Pink’s Assess Your Risk tool.)
How is DCIS diagnosed?
In general, women with DCIS do not have any symptoms. Providers typically discover DCIS through a screening mammogram, which can detect microcalcifications in the breast. These calcium deposits are only visible on mammography, and this imaging can provide an estimate for how much of the breast contains DCIS. An MRI can sometimes help to determine the extent of DCIS, but it can also overestimate the amount DCIS leading to more extensive surgery.
After finding microcalcifications, health providers will confirm that DCIS is present. The best way to confirm a diagnosis of DCIS is by performing a mammogram guided core needle biopsy. The provider will remove several small pieces of tissue from the breast and analyze them under a microscope to detect abnormal cells.
If DCIS is present, a pathologist will typically categorize the DCIS into Low (grade 1), Intermediate (grade 2) or High grade (grade 3) based on how fast the cells are growing and on their appearance. They will also measure two proteins, the estrogen receptor and progesterone receptor. This information can be useful in guiding treatment.
I was just diagnosed with DCIS. What do I do now?
Learning you have DCIS can seem overwhelming, but don’t panic. DCIS is not life-threatening and not an emergency. If you have this diagnosis, the first important step is to make an appointment with a surgeon who specializes in breast surgery to learn about your options for treatment.
The main reason to treat DCIS is to prevent it from coming back or becoming invasive breast cancer. If we leave DCIS alone, up to half of patients will develop invasive breast cancer.
We don’t know for sure which patients will develop invasive breast cancer or when. To be absolutely safe, we recommend removing the DCIS surgically with some normal breast tissue around it. This type of procedure is called a lumpectomy, wide local excision, or partial mastectomy.
The extent of surgery recommended by your surgeon depends on the amount of DCIS present and the location of the DCIS in your breast. More surgery is not necessarily better and should be weighed against the risk of surgical complications and long-term side effects. Have an open and clear conversation with your breast surgeon about your diagnosis and any potential side-effects or complications from the surgery to decide on a plan that’s right for you.
How soon do I need to have surgery?
You do not need to have surgery immediately. Again, DCIS is not an emergency. DCIS is pre-invasive and cannot spread. We think that only about 50% of DCIS cases will become invasive and the abnormal cells and surrounding tissues have to undergo many changes over time to become invasive. For most patients, this series of changes takes many months or years. It is safe to weigh different treatment options and consider a second opinion.
Do I need to have radiation after my surgery?
Breast radiation after surgery can reduce the risk of DCIS coming back by 50%. It is important to meet with a radiation oncologist to discuss the risks and benefits of radiation treatments. Newer tests are becoming available that may help physicians and patients tailor radiation therapy based on molecular characteristics of the tumor.
Why is my doctor recommending Tamoxifen?
Taking a medication such as Tamoxifen or an aromatase inhibitor, which work to slow the growth of abnormal cells, can reduce of the DCIS coming back by 30%. An added benefit is that the medication can also prevent a new breast cancer on the other breast.
What are the chances of DCIS coming back? What kind of follow-up do I need?
The chance of DCIS coming back depends on a number of factors. Your age, whether you used radiation or a medication like Tamoxifen, and whether your provider removed the DCIS with enough normal tissue around it can all affect your chances of having the DCIS return. DCIS can come back many years later as DCIS or invasive cancer. You should continue to get screening mammograms every year to make sure you are still cancer-free.
What are we learning about DCIS and how to treat it?
We are learning that treatment for DCIS is not “one size fits all.” Some women may need no treatment. There are large clinical trials going on in Europe, Asia, and the United States that are trying to answer the question of whether some women can undergo active surveillance with breast imaging and completely avoid surgery for DCIS.
There are also trials to determine if medications alone can be used to treat DCIS. The best way to figure this out is for women with a new diagnosis of DCIS to consider participating in a clinical trial in the period of time before they undergo surgery. These trials are called Window of Opportunity Trials and are typically 2-6 weeks long. It is safe to participate in these trials. Delaying your surgery for a short time will have no impact on your outcome. The results of these studies may allow some women to avoid surgery in the future.
*Refers to pure DCIS.