ERBB2 and breast carcinoma: Studies from Western countries indicate that breast cancer survival is low in patients with tumors that over express the human epidermal growth factor receptor-related gene ErbB2 (c-ErbB2, HER2, or neu).4,5 Tumors that over express ErbB2 are more likely to recur4,5 and are relatively resistant to many treatments.4 Two recently developed treatments that specifically target ErbB2, trastuzumab and lapatinib, are effective either alone or with chemotherapy in reducing tumor recurrence and mortality in patients with ErbB2-positive breast cancer.6