Women diagnosed with ductal carcinoma in situ (DCIS) face a more complicated array of choices than ever, based on a new Canadian study led by researcher Steven A. Narod. Ductal carcinoma in situ means that precancerous or cancerous cells were found within a milk duct in the breast but had not yet spread beyond the milk duct. Dr. Narod and his colleagues looked at the data for over 108,000 women diagnosed with DCIS between 1988 and 2011 and compared their mortality with women in the general population.
Twenty years after diagnosis about three percent of the women in the study had died from breast cancer while about five percent had died from other causes. One surprising finding of the study is that radiation following lumpectomy reduced the chance of an invasive cancer in that breast, but it did not reduce the twenty-year mortality rate. African-Americans and women diagnosed diagnosed before age 35 had higher mortality rates of about seven and almost eight percent respectively.
The study has renewed debate on the best way to treat DCIS. Currently, treatment often includes lumpectomy, radiation, and tamoxifen or an aromatase inhibitor. Some women even opt for bilateral mastectomies.
Which treatment is best for you?
This new information leads some doctors to suggest watchful waiting may be appropriate for some women with DCIS. Doctors in this camp point out that treatment itself has its own dangers. Complications from surgery and radiation and side effects from hormonal treatments may reduce quality of life for women whose DCIS is not life threatening. Others point out that worrying about whether DCIS will grow into a dangerous, invasive tumor also reduces quality of life.
What should you do if you have a DCIS diagnosis? First of all, don’t panic. Even for the highest risk groups in this study more than 90 percent were still alive twenty years later. Next you need to get more information about the characteristics of your particular DCIS. A larger tumor or multiple spots of DCIS suggest that more extensive treatment might be appropriate. The pathology report will give the grade of the cancer cells as well as features like their hormone receptor and HER2 status. From this information, your oncologist can make educated guesses about how aggressive the cancer is. Your age may also be a factor in how you interpret this information and the choices you make. A 73 year-old looking at 20 year survival statistics may decide on minimal treatment, while a 33 year-old who will be only 53 in 20 years may opt for more.
I doubt whether many women will choose watchful waiting. Most would find it pretty nerve-wracking to go for more frequent check-ups to see if those cells are spreading. Also there isn’t any clinical trial data on whether this is a safe approach. The women in the Canadian study had a minimum treatment of lumpectomy. But if your doctor thinks it is safe in your case, and you have particular reasons to want to avoid surgery and other medical interventions, it might be right for you.
Most women with DCIS will have some form of surgery. A lumpectomy will usually be what the doctor recommends. Some women think that a mastectomy will make them less worried about a later diagnosis of breast cancer. Before opting for this more extensive surgery, you need information about the risks of mastectomy. A mastectomy may lead to problems with lymphedema or shoulder problems later. However, if there are many spots of DCIS scattered throughout the breast, a mastectomy may be the only option.
Treatment after surgery
Currently radiation often follows surgery, but this is a treatment you may want to skip if you are at low risk, especially if you are over sixty. Radiation is the treatment that is most likely to cause side effects such as fatigue, lymphedema, or even another cancer. One long-term study found little benefit of radiation for women over sixty with Stage I hormone receptor positive breast cancer compared to surgery and hormonal treatments alone. This wasn’t a DCIS study, but combined with the new DCIS study, it is information that might lead you and your doctor to decide that you don’t need radiation.
Tamoxifen or an aromatase inhibitor is another option for treatment if the pathology report shows that the DCIS is hormone receptor positive. A big advantage of hormonal treatments is that they reduce the chance of an invasive breast cancer. They also are systemic treatments that target cancer anywhere in your body. One troublesome aspect of Dr. Narod’s study is that 517 women died of metastatic breast cancer even though they never had another cancer show up in their breast. In other words, despite their original diagnosis of DCIS, some cancer cells must have escaped the milk duct to spread to a vital organ. Although 517 is a tiny fraction of 108,000, it seems reasonable to try a systemic treatment for DCIS when appropriate.
A huge issue for you to consider is your own personality type. While the survival rate from DCIS is quite high, you know whether you are a worrier. It might be important to you to go with the most aggressive treatments for peace of mind. If you are uncomfortable with hospitals and medical procedures, you may prefer to go with the odds and assume that you will be in the vast majority of DCIS patients who do just fine with minimal treatments.
Although there are still too many guesses involved in making treatment decisions for DCIS, the good news is that patients now have more information to help them.
For further reading on breast cancer treatment:
Esserman L, Yau C. Rethinking the Standard for Ductal Carcinoma In Situ Treatment. JAMA Oncol. Published online August 20, 2015. Accessed from http://oncology.jamanetwork.com/article.aspx?articleid=2427488 September 11, 2015.
Lichtenfel, L. Len’s Lens: New DCIS Research Brings Knowledge. Medpage Today, August 26, 2015. Accessed from http://www.medpagetoday.com/Blogs/ThroughLensLens/53255 Sept. 11, 2015.
Love, S. Are All Appearances What They Seem? New Insights Into DCIS. Huffpost Healthy Living. August 21, 2015. Accessed from http://www.huffingtonpost.com/susan-m-love/are-all-appearances-what-they-seem-new-insights-into-dcis_b_8016528.html September 11, 2015.
Narod SA, Iqbal J, Giannakeas V, Sopik V, Sun P. Breast Cancer Mortality After a Diagnosis of Ductal Carcinoma In Situ. JAMA Oncol. Published online August 20, 2015. Accessed from http://oncology.jamanetwork.com/article.aspx?articleid=2427491 September 11, 2015.