Imaging of breast masses.

The American College of Radiology Breast Imaging and Reporting Data System (ACR BI-RADS) defines a mass as a space-occupying lesion seen in at least two projections. This article focuses on the management of breast masses with mammography and ultrasonography. Recommended work-up pathways are modified for nonpalpable masses, palpable masses in women over the age of 30, and palpable masses in women under the age of 30. The suggested protocols are based on scientific peer-reviewed literature whenever possible, but when evidence based studies are not available, the author relies on expert opinion.