Breast Cancer : Luminal A
Luminal A Subtype of Breast Cancer: Microscopic photo showing an intermediate grade invasive breast carcinoma. The tumor cells are positive for ER (estrogen receptor)(see insert), and negative for PR (progesterone receptor)(see inserts). HER2/neu is not overexpressed, and Ki-67 (proliferation rate) is low to intermediate. This subtype (ER+/HER2-) accounts for 40-70% of all breast cancers. Image courtesy of: Jian-Hua Qiao, MD, FCAP, Los Angeles, CA, USA.