[Actins and keratins in the diagnosis of human basal-like breast cancer].

The most common forms of luminal breast cancer (BC) were compared with basal-like and Her2/neu3+ BC. Their primary classification was based on morphological diagnosis and the expression of estrogen receptor (ER), progesterone receptor (PR), and Her2/neu receptors. Monoclonal antibodies to actins and keratins were used for the study. Basal-like BC cells (ER/PR/Her2/ neu-) were regularly stained with antibodies to basal keratins 5/6 and 17, smooth muscle alpha-actin, and p63. Luminal keratin 8 staining was reduced. The solid regions had beta-actin staining with disappearance in the scirrhous component. beta-actin and basal keratins were also observed in metaplastic BC with ER/PR/Her2/neu3+. Immunomorphology using cytoskeletal markers along with the expression of steroid hormone and Her2/neu receptors may be used in the diagnosis of basal-like forms of BC.