HER2 2+/FISH+) on the pathological complete response (pCR) rate and patient prognosis in HER2-positive breast cancer treated with neoadjuvant therapy(NAT).<h4>Methods</h4>This retrospective study analyzed the clinicopathological data of 308 breast cancer patients with pathologically confirmed HER2-positive status (HER2 3+ or HER2 2+/FISH+) who received NAT combined with targeted therapy at our hospital from January 2017 to December 2020. This evidence concerns the gene ERBB2 and breast cancer.