ERBB2 and invasive breast carcinoma: <i>Materials and Methods</i>: A total of 221 patients with clinically node-positive (cN+) HER2-positive invasive breast cancer, with nodal involvement confirmed by fine-needle aspiration or core needle biopsy, who received neoadjuvant therapy (NAT) and subsequently underwent surgery at three centers between January 2015 and January 2025 were retrospectively reviewed.