Benign and malignant apocrine lesions of the breast.

Apocrine differentiation occurs in a variety of breast lesions, both benign and malignant. This review is a reflection of our critical view of the recent advances towards the understanding of this particular type of breast lesions. Focus is given to the histological criteria that allow their reproductive identification, with additional attention to the recent microarray studies. These describe the recent molecular classification of breast cancer and identify an apocrine molecular subtype that opens the door for new putative therapies for this particular type of tumor. Indeed we anticipate that the determination of androgen receptor will enter into the routine assessment of breast cancer cases and become a surrogate marker for treatment in apocrine triple-negative breast cancer.