Suspicious Focal Asymmetry on Mammography

IMAGING FINDINGS: ​

​Standard craniocaudal and mediolateral oblique views of both breasts demonstrate a focal asymmetry in the upper outer left breast. There is suggestion of associated architectural distortion.

WHY IT MATTERS:

1. Focal asymmetries are a relatively common occurrence on a screening mammogram. They occur when the asymmetric density can be clearly seen on two views but lacks the convex borders of an actual mass.
2. The workup of a focal asymmetry includes additional mammographic or tomosynthesis views to confirm it is a true abnormality and not just overlapping tissue. If the finding persists, an ultrasound should be performed.
   
   
   

FURTHER READING:
Focal Asymmetric Densities Seen at Mammography: US and Pathologic Correlation (RadioGraphics 2002)