Breast MRI Screening for High-Risk Patients

Although mammography can reduce breast cancer mortality rates in screened populations, its modest sensitivity, especially in younger women with strong family histories for breast cancer, has prompted the introduction of breast magnetic resonance imaging (MRI) for high-risk screening. Seven prospective screening trials for high-risk patients in which MRI has been added to mammography indicate the sensitivity of MRI to be twice that of mammography alone. The specificity of MRI is lower than mammography in most, but not all studies; however, the specificity of MRI improves to a level comparable to mammography in screenings subsequent to the initial prevalence screen. Although the target populations in breast MRI screening studies have been identified by genetic and familial risks, the superior sensitivity of MRI has been demonstrated at all levels of elevated risk, raising the possibility that MRI screening could benefit women with risk factors other than a positive family history. The published studies on breast MRI screening are reviewed herein, along with new screening guidelines that are currently shaping practice patterns.