Immunodeficient mice bearing patient-derived trastuzumab- and lapatinib-resistant HER2+ breast tumors revealed that such refractory tumors respond well to the combination of pertuzumab and EGCG suggested by a considerable reduction in tumor size and apoptosis identified in tumor sections by the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method. Here, ERBB2 is linked to neoplasm.