Opposing Viewpoints on DCIS Treatment: Making Sense of the Controversy
A new study1, presented at the 2016 annual meeting of the American Association for Cancer Research, asserts that women who had treatment for ductal carcinoma in situ (DCIS) were at higher risk of developing malignant breast tumors if they did not receive timely radiation therapy as part of their treatment. Further, the researchers are urging women to consider the benefits of timely radiation therapy after breast-conserving surgery, or lumpectomy.
Some background on DCIS
Ductal carcinoma in situ is a noninvasive breast abnormality — a collection of abnormal cells in the lining of the breast duct. It is the most common premalignant (meaning non-cancerous) breast lesion. Over 60,000 women are diagnosed each year. Not all DCIS develops into invasive cancer. However, because there is a concern that a small proportion of DCIS lesions could become invasive, most women diagnosed with DCIS currently undergo some form of treatment for it.
According to treatment guidelines established by the National Comprehensive Cancer Network2, treatment for DCIS generally includes one of three options:
- Lumpectomy (also called breast-conserving surgery)
- Lumpectomy followed by radiation therapy (a combined treatment sometimes referred to as breast-conserving therapy)
Over the past several years, a growing body of evidence is causing some researchers to re-evaluate how DCIS is treated. Or at least commission more studies to find out if new treatment options are warranted.
One such study, a 2015 observational study involving more than 100,000 women and published in JAMA Oncology3, suggests that, while treating DCIS may help prevent a recurrence in the breast, it does not appear to decrease the already-low risk of dying from the disease, even after 20 years of follow-up.
Most women who participated in the study received either a lumpectomy (with or without radiation therapy) or a mastectomy. The overall death rate from breast cancer at 20 years after diagnosis was 3.3% — a rate similar to that of the general population. This was true regardless of the type of treatment used.
There is one caveat to consider. Some women with DCIS may be at an increased risk of dying from breast cancer, including those diagnosed at a younger age and African Americans, according to study findings. Death rates were higher for women diagnosed before age 35 than for older women, and higher for African Americans than for Caucasians.
What’s the harm in treating DCIS?
Just like all cancer treatments, treatments for DCIS do carry potential risks. For instance, exposure to radiation therapy increases the risk of developing secondary cancers in the future. And any type of surgery — including lumpectomy and mastectomy — can cause health problems as well.
Some final thoughts
Some physicians have suggested that treatment for DCIS may go the way of treatment for some early-stage prostate cancers. That is, close monitoring of the precancerous lesions, with treatment if there is any progression. This approach is called active surveillance.
Is active surveillance a viable option for DCIS? Well, the jury’s still out on this one.
While some physicians may recommend active surveillance for DCIS, more research is needed to compare the outcomes of current treatments against active surveillance before it can become a standard of care. In the meantime, other doctors have suggested a compromise – lumpectomy to remove the lesions, without the potentially damaging radiation.
For now, it’s best to have a thorough discussion with your doctor about the risks and benefits of all your treatment options in light of your specific disease pathology and recurrence risk before deciding on a course of action.