ERBB2 and breast carcinoma: The recognition of human epidermal growth factor receptor type 2 (HER2, Gene Symbol HER2; located on chromosome 17q12) over-expression as a therapeutic target for advanced breast carcinoma was primarily related to the clinical finding that HER2/neu proto-oncogene is amplified in 15–25% of all breast tumors, and is often associated with poor disease-free survival (DFS) [8-15].