RecruitingPhase 2Drug trialTrastuzumab Deruxtecan Versus Standard Neoadjuvant Treatment for HER2-positive Breast CancerThe goal of this clinical trial is to compare trastuzumab deruxtecan (T-DXd) to standard preoperative treatment in patients with non-metastatic HER2-positive breast cancer. The main questions it aims to answer are: * is T-DXd more effective than standard preoperative treatment? * are there markers in the tumor or blood of patients with HER2-positive breast cancer that can help us predict response to treatment? Participants will be divided into two groups, where one group will be treated with three courses of T-DXd and the other group will be treated with three courses standard of care treatment. Thereafter, further treatment will be decided by the tumor's molecular subtype.