Each year, about 60,000 women in the U.S. are diagnosed with an early stage of breast cancer called ductal carcinoma in situ (DCIS). Many of them undergo surgery, radiation and hormonal therapy to combat the cancer. A recent study, however, raised questions about what the most appropriate and effective treatment approach is for DCIS.
What is DCIS?
DCIS, which some oncologists call stage 0 cancer, is an uncontrolled growth of cells within the milk ducts in the breast. It’s a non-invasive form of cancer, which means that it has not spread into tissue outside of the ducts. DCIS currently accounts for about 1 in 5 new breast cancer diagnoses in the U.S. Unfortunately, DCIS is not easy to diagnose. In one well-designed recent study 13 percent of DCIS cases were misdiagnosed as less serious, while 3 percent were mistaken for invasive cancer.
DCIS does not usually create a lump in the breast, so about 80 percent of cases are discovered during routine mammography, then confirmed by needle biopsy. A small percentage of women experience breast pain and nipple discharge before they are diagnosed. The majority of women with DCIS undergo a lumpectomy, sometimes followed by radiation. Most of the remaining women diagnosed with DCIS undergo mastectomy.
Deciding which treatment path to follow
The decision of which treatment approach to follow involves a combination of important factors: personal preference, grade of tumor (higher grade is more likely to recur), risk tolerance and bias of the treating physician. Mastectomy has the lowest rate of reoccurrence and does not generally require radiation treatment. But it does not necessarily change long-term survival. Women who have lumpectomies (with or without radiation) have a higher rate of local recurrence, which requires another surgery, but they have the same rate of long-term survival. In other words, in most cases these recurrences are detected at an early stage.
The recent study examined retrospective data from 100,000 women followed over 20 years. The researchers found no difference in death rate from breast cancer between the women who had a lumpectomy with or without radiation and those who underwent mastectomy. Only about 3.3 percent of the women in the study died of breast cancer, a rate that is similar to an average women’s risk of dying of the disease. The results raised a question—are women undergoing mastectomy for a condition that could be treated just as effectively with a less invasive approach?
The study, which was not a double-blind, controlled study, did not provide the data needed to answer that question. In fact, other studies have linked lumpectomy and radiation to a higher risk of recurrence of the tumor in the same area than mastectomy, so it’s important to talk with your physician about your specific risk factors and appropriate treatment options.
You should also ensure that you have the correct diagnosis and that you are fully and objectively informed about the risks and benefits of different treatment options. Finally, there is a relatively new genetic test available that uses a sample of tissue from the tumor and measures the activity level of a group of cancer genes in that tissue to develop a projection of how likely it is that the tumor will recur or will return as invasive breast cancer. Patients, in consultation with their treating physician, can consider adding this personalized genetic information to the information they use to choose a treatment path.
Questions to ask your doctor after a DCIS diagnosis
If you or a loved one has been diagnosed with DCIS, the first step is to get a second opinion. You should also ask your physician these questions to gather as much information as possible about your diagnosis and treatment options:
- How is DCIS different from invasive breast cancer?
- How large is the area of DCIS and is there more than one area?
- What treatment approach do you recommend and how effective is it in women with DCIS?
- What side effects and complications can the treatment cause?
- What is the likelihood of this cancer recurring or spreading?
- Is my DCIS estrogen receptor-positive or –negative and will I need hormone therapy as part of my treatment?
- What are my treatment options if it does recur?
- How quickly do I need to make treatment decisions?
With this information and your doctor’s advice, you can make a more informed cancer treatment decision.