Introduction: Asymmetric breast tissue is a relatively common mammographic finding and is usually benign. It might be due to a normal variation, postoperative changes or hormone replacement therapy. However, an asymmetric area may indicate a developing mass or an underlying cancer.
Method: We collected random cases of asymmetric breast densities on mammography, and present examples of the four types according to the recent ACR BIRADs classification. The four types are global asymmetry (previously known as asymmetric breast tissue), asymmetry (previously known as density seen on one projection), focal asymmetry (previously known as focal asymmetric density) and a developing asymmetry (replacing architectural distortion). The final diagnoses are given, confirmed on further investigations such as biopsy and FNAC or supplementary imaging.
Conclusion:
Accurate interpretation of breast asymmetry found on a mammogram may needs additional imaging studies such as supplementary views, ultrasonography or magnetic resonance imaging. Radiologist should be aware of this condition and further assessment should be carried out in a logical work flow for optimum patient care
