Starting from these considerations, we designed an observational retrospective study aimed at comparing in real life, in terms of pCR, sequential anthracyclines and taxanes plus trastuzumab (ATH) with pertuzumab, trastuzumab plus taxanes (THP) as neoadjuvant treatment in patients with HER2-positive early BC (EBC). The gene discussed is ERBB2; the disease is breast cancer.