ERBB2 and breast cancer: With this awareness of the limitations stemming from the retrospective nature of our prior study in Her2+ locally advanced BC and in light of the previously cited evidence from pre-clinical and clinical studies carried out by other research groups and ours, we designed this multicentric, prospective study to investigate the impact of key components of the Hippo pathway on pCR in locally advanced BC patients treated with trastuzumab-based neoadjuvant regimens.