Fig. 1

Hematoxylin and Eosin (H&E) slide of a case of invasive carcinoma of the breast with a characteristic apocrine morphology; the tumor cells are negative for ER-α66 (ER), but stain positively for androgen receptor (AR). Her-2/neu protein was overexpressed exhibiting a complete, intense membrane positivity in the majority of neoplastic apocrine cells (HER2).