Asymmetries in Mammography

In mammography, an asymmetry is an area of increased density in 1 breast when compared to the corresponding area in the opposite breast. Most asymmetries are benign or caused by summation artifacts because of typical breast tissue superimposition during mammography, but an asymmetry can indicate breast cancer. Detection and diagnosis of asymmetries is challenging because they often are subtle and appear similar to typical fibroglandular tissue in the breast. During screening mammography, asymmetries discovered that are not summation artifacts require further evaluation, such as diagnostic mammography, sonography, breast magnetic resonance imaging, or biopsy.