A new study is adding further fuel to the fire in the debate over how to treat early stage breast cancer called ductal carcinoma in situ (DCIS) or “0 Stage Cancer.”
The study, which appeared in the August issue of the Journal of the American Medical Association (JAMA) Oncology, revealed that women treated for DCIS were not significantly less likely to die of breast cancer than the average woman. The researchers found that the 20-year breast cancer death rate for women diagnosed was 3.3 percent. However, the death rate was higher for women diagnosed before age 35 and for black women.
What is DCIS?
More women are being diagnosed with DCIS – which was rarely diagnosed before the advent of mammography - because of increased screening and better imaging techniques. This year about 60,000 U.S. women will be diagnosed with DCIS, while more than 230,000 women are expected to be diagnosed with invasive breast cancer.
DCIS is a noninvasive condition in which abnormal cells are found in the lining of a breast duct. The abnormal cells have not spread outside the duct to other tissues in the breast. It is considered a pre-cancer because some cases can progress to invasive cancers.
How should DCIS be treated?
Some doctors support the study as evidence that women are being over-treated, while others believe women should be treated aggressively for what some doctors consider to still be a potentially dangerous and lethal cancer. The problem is that more research needs to be done to understand which cases will go on to become invasive and which ones won’t.
Standard treatment today involves several options such as a lumpectomy followed by radiation, a lumpectomy alone, mastectomy, or long-term hormonal therapy. What is to be noted, however, is that an increasing number of women today are opting for mastectomy or double mastectomy after a diagnosis of DCIS.
In a thoughtful article on Dr. Len’s Cancer Blog, he writes that while the study may have brought knowledge, he is not so certain the study has clarified understanding and may have confused women over what to do.
“The distinction is important, because when a woman is confronted with a diagnosis of a ‘Stage 0’ breast cancer or DCIS, the decisions she makes about treatment can have far-reaching and long-lasting impact for her and those who care about her,” wrote Dr. Len, who is J. Leonard Lichtenfeld, deputy chief medical officer for the American Cancer Society.
How does Baystate handle DCIS treatment decisions?
Dr. Seth Kaufman, director, Breast Radiation Oncology at Baystate Health, who is the primary author of the 2015 update of the American College of Radiology Appropriateness Criteria for Management of DCIS, offers his insight into the debate:
Management decisions for DCIS can be complicated, precisely because it is a pre-invasive cancer which does not pose a life-threatening danger.
As this study highlights, the diagnosis of DCIS does not appear to alter a woman's overall survival, but it can be a risk factor for later development of invasive breast cancer. Behavior of DCIS varies widely depending on factors such as grade (how rapidly tumor cells are growing and how much they have changed their appearance from normal breast cells), responsiveness to the natural hormones estrogen and progesterone (which correlates with responsiveness to hormone drugs like tamoxifen), how large an area the DCIS occupies, and a woman's age at the time of diagnosis.
At the Baystate Regional Cancer Program, we have incorporated factors including these into a set of well-vetted guidelines to help doctors and patients decide together how much or how little treatment is appropriate. Our guidelines continue to evolve as developing evidence , such as this study, help shape the national debate.