For Most with DCIS, Less Is More

For women diagnosed with ductal carcinoma in situ (DCIS), the likelihood of dying from breast cancer is very low but is increased substantially if invasive disease develops. To determine what factors predict breast cancer mortality in DCIS patients and whether aggressive treatment to prevent invasive recurrence reduces disease mortality, investigators conducted an observational study of more than 180,000 women (median age, 53.8) in the Surveillance, Epidemiology, and End Results database who were newly diagnosed with DCIS between 1988 and 2011.

At mean follow-up of 7.5 years, breast cancer–specific mortality at 20 years was 3.3% overall; however, for those who developed subsequent ipsilateral, invasive breast cancer, the risk for dying was 1…