ERBB2 and breast carcinoma: To date, successful examples of this newer drug discovery approach are noteworthy, and just to mention a few we site dramatic results with the use of bcr-abl- and c-kit-targeting agents on chronic granulocytic leukemia and gastrointestinal stromal tumors, the impressive results of Epidermal growth factor receptor (EGFR) inhibitors in a small subset of non-small-cell lung cancer, and the efficacy of targeting HER2 by a monoclonal antibody in approximately 30% of patients with breast cancer whose tumors overexpress this oncoprotein.