What is your approach to oligometastatic HER2 positive breast cancer, particularly after excellent clinical response in all sites of disease to trastuzumab, pertuzumab, and a taxane?

The question of optimal treatment of low burden metastatic HER2-positive breast cancer and complete or near complete response to systemic therapy remains open. The two potential strategies are to continue systemic therapy with HER2-blocking antibodies +/- endocrine therapy or to continue the systemi...