DCIS Tied to Higher Risk for Invasive Breast Cancer, Mortality

By Kelly Young

Edited by Susan Sadoughi, MD, and Richard Saitz, MD, MPH, FACP, DFASAM

Women with ductal carcinoma in situ (DCIS) detected on screening are at elevated risk for subsequent invasive breast cancer and breast cancer-related mortality relative to the general population, according to a study in The BMJ.

Using data from a national breast cancer screening program in England, researchers studied all 35,000 women diagnosed with DCIS, roughly two thirds of whom had been followed for over 5 years.

Among the findings:

• Invasive breast cancer was diagnosed in 8.82 per 1000 women with DCIS per year. The rate was more than double that expected in the general population, with the increase beginning in the second year following DCIS diagnosis.

• Among those developing invasive cancers, roughly 1.26 per 1000 women per year died from breast cancer — a rate 70% higher than expected.

• Women who had mastectomy had lower rates of ipsilateral invasive breast cancer, compared with those who had breast-conserving surgery with radiotherapy (adjusted rate ratio, 0.65). But those who had breast-conserving surgery with no radiotherapy were at higher risk (ARR, 1.43).

For more on the clinical implications of this study, stay tuned for Dr. Laila Samiian's summary in NEJM Journal Watch Women's Health.