Moreover, the presented findings could provide a novel strategy, beyond the conventional evaluation of HER2 expression, for predicting the patients who are most likely to achieve a pCR with preoperative trastuzumab-based systemic therapy; it may be possible to identify patients who are likely to achieve a pCR by evaluating the status of HER2 expression on tumor-infiltrated immune cells (Figure 4). This evidence concerns the gene ERBB2 and neoplasm.