Figure 1

Appearance of the bilateral breast cancers at pre- and post- treatment. The right breast cancer was defined HR-positive and HER2-negative status at pre-treatment (a). After neoadjuvant chemotherapy, the right breast cancer presented no significant change (b). The left breast cancer was defined HR-negative and HER2-positive at pre-treatment (a). After neoadjuvant chemotherapy with trastuzumab, the left breast cancer revealed significant reduction (b).