How would you approach adjuvant treatment of an early stage HR+ HER2+ cancer if the patient had already been taking an aromatase inhibitor for a contra-lateral HR+ early stage breast cancer?

My preference would be to recommend local and systemic treatment based on the newly diagnosed breast cancer, including its final pathologic staging and other clinically relevant features. If chemotherapy is needed, I would hold endocrine therapy. When the time comes to resume endocrine therapy, my p...

This patient’s contralateral breast cancer is a new primary and should be treated as such. Based on the APT trial data (Tolaney S et al NEJM), smaller HER2+ tumors will benefit from a single agent paclitaxel (12 weeks) + trastuzumab (one year) based regimen followed by adjuvant XRT (when recommended...

Consider clinical trial with a CDK inhibitor after completion of HER2 based chemotherapy, Or consider adjuvant Tamoxifen.