trastuzumab emtansine (n=119) vs. trastuzumab plus endocrine therapy (n=129)
randomized controlled trial
trastuzumab emtasine
trastuzumab emtasine: 3.6mg/kg every 3weeks for 4 cycles
trastuzumab plus endocrine therapy
trastuzumab: at a loading dose of 8 mg/kg and then 6 mg/kg every 3 weeks for 3 more cycles / endorine therapy: tamoxifen in premenopausal women and aromatase inhibitors in postmenopausal women
Gonadotropin-releasing hormone analogs were allowed in premenopausal patients
es-BC - HR positive - (neo)adjuvant (NA)
Exclusion criteria: nonoperable and inflammatory BC
open label
48 centers
P2 / 2 one-sided tests or proportions (arm A v arm C and arm B v armC) were planned at an a of .025 under the assumption of at least 25% pCRin both T-DM1 arms (arms A and, B), compared with a 10% pCR rate in the trastuzumab arm (arm C)