ERBB2 and invasive breast carcinoma: Present in approximately 20–25% of invasive breast cancers (IBC) (Meric et al., 2002), overexpression of the HER2 receptor tyrosine kinase is associated with more advanced stage disease at presentation and a rapidly progressive clinical course, including enhanced local-regional extent, early metastatic spread, and resistance to chemotherapy (Pohlmann et al., 2009), all of which contribute to poor clinical outcomes.