Not all with dense breasts have high interval cancer risk

(HealthDay)—Not all women with high breast density have high risk of interval cancer, according to a study published in the May 19 issue of the Annals of Internal Medicine.

Karla Kerlikowske, M.D., from the University of California in San Francisco, and colleagues conducted a prospective cohort study to examine which combinations of breast cancer risk and breast density correlate with high interval cancer rates. Data were included for 365,426 women, aged 40 to 74 years, who underwent 831,455 digital screening mammography examinations in Breast Cancer Surveillance Consortium (BCSC) breast facilities.

The researchers found that women with BCSC five-year risk of 1.67 percent or more and extremely dense breasts or five-year risk of 2.50 percent or more and heterogeneously dense breasts (24 percent of all women with dense breasts) had high interval cancer rates. Women with five-year risk of 2.50 percent or more and heterogeneously or extremely dense breasts (21 percent of all women with dense breasts) had the highest interval rate of advanced-stage disease (>0.4 case per 1,000 examinations). For 51.0 percent of women with heterogeneously dense breasts and 52.5 percent with extremely dense breasts, five-year risk was low to average (0 to 1.66 percent).

"Breast density should not be the sole criterion for deciding whether supplemental imaging is justified because not all women with dense breasts have high interval cancer rates," the authors write.