Focal Asymmetry on Mammography

IMAGING FINDINGS: ​

​MLO and CC views of the right breast demonstrate a focal asymmetry in the upper outer quadrant at a posterior depth. 
 
WHY IT MATTERS:

1. A focal asymmetry is a relatively common finding on mammography. It is defined as a lesion seen on two mammographic views (both CC and MLO). It has concave borders and lacks features of a true mass.
2. Focal asymmetry that persists on diagnostic mammography requires further sonographic evaluation and potentially percutaneous sampling.
   
   
   

FURTHER READING:

•  ACR BI-RADS® Atlas Fifth Edition QUICK REFERENCE
• Focal Asymmetric Densities Seen at Mammography: US and Pathologic Correlation (RadioGraphics 2002)