Are there other types of breast cancer screening modalities? Which modalities are used in everyday clinical practice?
Digital mammography is the standard today. Film screen mammography is slowly being phased out in clinical practice. Based on the digital platform, digital breast tomosynthesis (DBT) imaging can also be performed. In DBT imaging, multiple images are acquired through the breast over a range of angles resulting in reconstruction of 9 to 25 images. Instead of one image, multiple images are generated for each mammographic view. Studies to date have demonstrated improved lesion conspicuity for suspicious masses and architectural distortion across all breast densities with DBT.
Screening breast ultrasonography (US) consists of examination of both breasts in asymptomatic women. The largest prospective study to date was sponsored by the American College of Radiology Imaging Network (ACRIN). The goal of the prospective, multicenter trial was to compare the diagnostic yield of screening mammography plus US versus screening mammography alone in high-risk women. Although screening US examinations found additional breast cancers, there were also some false-positive results.
Screening magnetic resonance imaging (MRI) is not likely to be used in everyday clinical practice for the average risk woman because of the lack of availability, high cost, and potential for false-positive interpretations. However, MRI screening is used to screen very high-risk patients. The average woman has approximately 12% lifetime risk of being diagnosed with breast cancer. The American Cancer Society guidelines recommend MRI screening in women with a greater than 20% to 25% lifetime risk for breast cancer. The screening groups include women who are carriers of the BRCA mutations or untested women with a first-degree relative who is a known carrier; women with a history of mantle field radiation before age 30; and women with Li-Fraumeni, Cowden, and Bannayan-Riley-Ruvalcaba syndromes. MRI screening cancer yield in high-risk patients has consistently been 2% to 3%.