Breast Hamartoma

IMAGING FINDINGS: ​

Craniocaudal and mediolateral oblique views of the left breast show a large circumscribed mixed density mass occupying the upper outer quadrant. There are fat, calcifications and soft tissue density components to the mass. 
 
WHY IT MATTERS:

1. Breast hamartomas (or fibroadenolipomas) are a benign proliferation of fibrous, glandular, and fatty tissue surrounded by a thin capsule of connective tissue. 
2. Hamartoma’s contain all the components found in normal breast tissue, which is why the lesions have a “breast within a breast” appearance.
3. The presence of multiple hamartomas can be seen with Cowden’s Syndrome.

FURTHER READING:
Unusual Breast Lesions: Radiologic-Pathologic Correlation (RadioGraphics 1999)