Women diagnosed with ductal carcinoma in situ (DCIS) are at twice the risk of dying from breast cancer compared with women in the general U.S. population, according to a new study published online in JAMA Oncology.
Dr. Steven Narod of the Women's College Research Institute in Toronto and colleagues investigated data from more than 100,000 U.S. women who had been diagnosed with DCIS (JAMA Oncology, August 20, 2015).
The team found that about 1.1% of women died of breast cancer within 10 years of being diagnosed with DCIS, and about 3.3% of women died of breast cancer within 20 years of being diagnosed with the disease. The study also found the following:
- Women diagnosed with DCIS before the age of 35 were 17 times more likely to die from breast cancer within 10 years compared with women in the general U.S. population.
- Black women had a higher risk of dying from breast cancer within 20 years of being diagnosed with DCIS compared with white women.
- Women with DCIS who later developed an invasive form of cancer in the same breast were 18.1 times more likely to die of breast cancer.
- 54.1% of women with DCIS who died of breast cancer did not have an invasive in-breast recurrence of cancer prior to death.
"Our work shows that DCIS has more in common with small invasive cancers than previously thought," Narod said in a statement released by the institute. "In these cases, we've found that there's an inherent potential for DCIS to spread to other organs."
