Use validated tools to assess risk comprehensively
Women aged 50 to 74 with extremely dense breasts have reduced interval cancers following a normal biennial mammogram if supplemental MRI is offered, but the long-term benefit of identifying these cancers earlier is unclear. Until more data are available on important long-term outcomes (such as breast cancer mortality and need for more invasive treatments), providers should consider breast density in the context of a more comprehensive assessment of breast cancer risk using a validated breast cancer risk assessment tool.
I prefer the modified version of the International Breast Cancer Intervention Study (IBIS) tool, which is readily available online (https://ibis.ikonopedia.com/).7 This tool incorporates several breast cancer risk factors, including reproductive risk factors, body mass index, BRCA gene status, breast density, and family history. The tool takes 1 to 2 minutes to complete and provides an estimate of a woman’s 10-year risk and lifetime risk of breast cancer.
If the lifetime risk exceeds 20%, I offer the patient supplemental MRI screening, consistent with current recommendations of the National Comprehensive Cancer Network and the American Cancer Society.8,9 I generally recommend starting breast imaging screening 7 to 10 years prior to the youngest breast cancer occurrence in the family, with mammography starting no earlier than age 30 and MRI no earlier than age 25. Other validated tools also can be used.10-13
Incorporating breast density and other important risk factors allows a more comprehensive analysis upon which to counsel women about the value (benefits and harms) of breast imaging.8