A large observational study of more than 100,000 women has found that while the risk of dying from breast cancer after a ductal carcinoma in situ (DCIS) diagnosis is quite low, it is on par with the mortality rate of women diagnosed with small, invasive breast tumors. The study also found that aggressive DCIS treatment does not produce better results. These results are published in JAMA Oncology.
Steven A. Narod, MD, of the Women’s College Hospital, in Toronto, Canada, and coauthors used the Surveillance, Epidemiology, and End Results (SEER) 18 registries database to identify women diagnosed with DCIS between 1988 and 2011. The risk of dying of breast cancer among these women was compared to that of the general population. The average age at DCIS diagnosis was 53.8, and the women were followed for an average of 7.5 years.
DCIS is often described as a “pre-invasive neoplastic lesion that is not lethal in itself,” according to the authors, but “the results of the present study suggest that … cases of DCIS have more in common with small invasive cancers than previously thought.”