In a patient with ER+/HER2+ breast cancer with significant residual disease post neoadjuvant TCHP, is there a role of using CDK4/6i in the adjuvant setting with T-DM1?   

This is an open question. As has been true in oncology for some time, most of the adjuvant therapies we offer have shown benefit first in the metastatic setting, and then are tested in the adjuvant setting. Abemaciclib has been shown to have benefit when combined with herceptin and endocrine therapy...