Pleomorphic adenoma of the breast.

The clinicopathologic features of 2 new and 24 previously reported cases of pleomorphic adenoma of the breast are reviewed. This benign breast tumor resembles its salivary gland counterpart histologically. The circumscription and preferential juxta-areolar location suggest large breast duct origin of the tumors. Inappropriate surgery, i.e., mastectomy, was performed in 42% of the cases. Misdiagnosis and the resulting inappropriate treatment can easily be avoided if the pathologist includes this entity in the differential diagnosis when confronted with unusual differentiated epithelial breast lesions.