De-escalation chemotherapy strategy with the use of T-DM1 plus pertuzumab against taxane with pertuzumab and trastuzumab, after anthracycline-based chemotherapy, failed to meet the iDFS primary endpoint in the phase III KAITLIN study for HER2-positive eBC (node-positive or node-negative, HoR-negative and tumor size >2.0 cm) [69]. Here, ERBB2 is linked to neoplasm.