Changes in the copy number aberration(CNA) landscape of luminal B HER2- negative (HER2−) breast cancer (BC)during anthracycline-based neoadjuvant chemotherapy (NAC) regimens were studiedin order to identify groups of potential CNA markers of objective response andCNA markers for predicting the development of hematogenous metastasis.Comparison of CNA frequencies depending on the response to NAC showed thatobjective response was observed in a larger number of deletions in the 11q22.3and 11q23.1 loci (p = 0.004). This evidence concerns the gene ERBB2 and breast cancer.