ERBB2 and breast cancer: First, the KRISTINE study revealed that the neoadjuvant systemic chemotherapy (docetaxel, carboplatin) plus dual HER2 blockade (trastuzumab plus pertuzumab) achieved a higher rate of pathological complete response (pCR) compared to T-DM1 plus pertuzumab (55.7% vs 44.4%).30 Subsequently, the Neopeaks study compared docetaxel + carboplatin + trastuzumab + pertuzumab (TCbHP) for six cycles or TCbHP for four cycles, followed by trastuzumab emtansine + pertuzumab (T-DM1 + P) for four cycles or T-DM1 + P for four cycles in patients with HER2-positive early primary breast cancer.