With the increased interest in a more personalized approach to the management of this disease, including the DECRESCENDO trial [NCT04675827], the REaCT team is interested in performing a novel, pragmatic clinical trial of 6 months of anti-HER2 therapy in HER2-positive EBC patients with low-risk disease, defined by the absence of tumor in the breast and lymph nodes at the time of surgery, following neoadjuvant systemic chemotherapy and anti-HER2 therapy [24]. This evidence concerns the gene ERBB2 and neoplasm.