How would you approach systemic therapy in a postmenopausal female with previous early stage ER/PR positive IDC, on anastrozole, with new isolated metastatic disease that remains strongly ER/PR positive?

For the typical patient with disease recurrence (and measurable or evaluable disease) on adjuvant AI, the standard of care would be to switch endocrine therapies, usually from the AI to fulvestrant, and add a CDK 4/6 inhibitor, though simply adding the CDK 4/6 inhibitor to the AI would also be reaso...