Similar or better balance of benefits and harms were observed in average-risk women aged ≥50 years with low breast density undergoing triennial screening and higher-risk women with high breast density receiving annual screening when compared to average-risk women receiving biennial screening. This according to a collaborative simulation screening modeling of women aged ≥50 years with various combinations of breast density and relative risk (RR) of 1.0, 1.3, 2.0, or 4.0. Interventions included annual, biennial, or triennial digital mammography screening from ages 50 to 74 years (vs no screening) and ages 65 to 74 years (vs biennial digital mammography from ages 50 to 64 years). Researchers found:
• Breast cancer deaths averted were similar for triennial vs biennial screening for both age groups (50 to 74 years and 65 to 74 years) among women with fatty breasts or scattered fibroglandular density and an RR of 1.0 or 1.3.
• Breast cancers deaths averted increased with annual vs biennial screening for women aged 50 to 74 years at all levels of breast density and an RR of 4.0 and those aged 65 to 74 years with heterogeneously or extremely dense breasts and an RR of 4.0.
• Conversely, harms were nearly 2-fold higher.
Citation: Trentham-Dietz A, Kerlikowske K, Stout NK, et al. Tailoring breast cancer screening intervals by breast density and risk for women aged 50 years or older: Collaborative modeling of screening outcomes. [Published online ahead of print August 23, 2016]. Ann Intern Med. doi:10.7326/M16-0476.