Original Investigation July 8, 2021 JAMA Oncol. 2021;7(9):e212140. doi:10.1001/jamaoncol.2021.2140 Key Points Question What are the real-world survival outcomes associated with use of pertuzumab and trastuzumab emtansine (T-DM1) for ERBB2-positive metastatic breast cancer? Findings In this cohort study of 795 women in Ontario, Canada, median survival with pertuzumab (43 months) and T-DM1 (15 months) were substantially shorter than outcomes reported in previous pivotal trials.
