ERBB2 and cancer: In the ACOSOG Z1071 trial the highest pCR rates in both the breast and axilla were seen in HER2 positive cancers at 45.4%, followed by triple negative cancers at 38.2%, whereas the pCR rate was only 11.4% in the hormone-receptor positive category [14] The overall pCR rate of 17.2% in our study was in accordance with the expected rates taking in consideration that approximately two thirds of our study population were hormone-receptor positive [14].