What would you recommend as the next line treatment in a post-menopausal woman with hormone receptor positive, HER2 positive breast cancer, with progression on T-DM1 in combination with aromatase inhibitor?

Depending on the extent of disease and degree of symptoms and other prior therapies (e.g. she had trastuzumab and pertuzumab) prior to T-DM1, one could either choose tucatinib/trastuzumab/capecitabine—or if less ill or less heavily involved or asymptomatic with less disease, fulvestrant and trastuzumab with or without pertuzumab, depending on prior exposure to pertuzumab.