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?  

Specifically, this patient had a new left lacrimal gland metastatic lesion that developed four years from her initial diagnosis and is currently undergoing proton therapy to this lesion. No other evidence of disease with imaging. 



Answer from: Medical Oncologist at Academic Institution