An article published this week might raise concerns, again, for women who have been diagnosed with ductal carcinoma in situ (DCIS). This is cancer in the milk ducts of the breast. This type of breast cancer is generally non-invasive, which means that it is only in the milk duct. But in some cases the tumor grows beyond the duct, which makes it invasive.

The study, published in JAMA Network Open and conducted by Women’s College Research Institute, Women’s College Hospital, in Toronto, Canada, looked at the number of deaths from breast cancer in women who had been diagnosed with DCIS between 1995 and 2014. Their finding was that those with DCIS were significantly more at risk of dying of breast cancer than those who did not have DCIS. The researchers said there was a 3-fold increase in risk.

A similar study from Women’s College Hospital, published in 2015, showed comparable results. This current study “is really an update” and “part of a larger project” to better understand breast cancer, said Steven Narod, MD, a researcher in the 2020 and 2015 studies. But what the current study also showed is that “These findings suggest that the current treatment of DCIS does not eliminate the risk of breast cancer mortality.”

A Word About DCIS

DCIS is often felt as a lump in the breast and can be diagnosed on a mammogram. A suspicious mammogram will lead to a biopsy of the suspicious area. DCIS can be treated by

lumpectomy, in which the cancerous area alone is removed, followed by radiation therapy, or mastectomy, when the entire breast is removed.

If the DCIS is confined to the duct, chemotherapy is not required. For women under age 40 and women with advanced stages of DCIS, more aggressive treatment may be required as the risk of the cancer coming back is higher in these cases.

The Study

What the researchers found suggests that Black women and women under 40 were at greater risk of dying from breast cancer. This is the same information from the study 5 years ago.

According to the Breast Cancer Research Foundation (BCRF), white women are more likely to be diagnosed with breast cancer and Black women are more likely to die from breast cancer. The reasons for this are complicated and research is ongoing to find out more about these differences.

The researchers in the 2020 JAMA study found that women who received radiation therapy after lumpectomy lived longer than those who had just the lumpectomy. Those who had a mastectomy most likely had large advanced tumors.

The 2015 Study

This study included women who had been diagnosed younger than 35 years of age, and women who had been diagnosed with DCIS between 1988 to 2011. It found no evidence of reduced screening or inadequate treatment that could be attributed to the increased number of deaths in Black women.

Dr. Narod said the results of both studies are consistent in that with DCIS the age of diagnosis and race are factors related to the increased deaths.

In other words, Black women tend to die more often from breast cancer, and as people age the chances of getting breast cancer increase. So women who are diagnosed under 40 years of age have an increased likelihood of getting breast cancer again.

Lack of Recommendations

The researchers did not recommend any changes to the treatment of DCIS due to these results. They also did not recommend the routine addition of chemotherapy for DCIS patients as the lifetime risk of death from DCIS is 3%. The real problem is how to know which patients have the highest risk of dying after a DCIS diagnosis.

Yvonne Stolworthy MSN, RN graduated from nursing school in 1984 and has had a varied career. Many years were spent in critical care. She has been an educator in a variety of settings, including clinical trials. Currently she is applying her nursing knowledge to health care journalism.