Does the degree of ER/PR positivity influence your treatment option in the patient with newly diagnosed metastatic breast cancer?

There is robust evidence showing that breast tumors with a low percentage of hormone receptor expression derive a smaller benefit from endocrine therapy compared to patients with strong hormone receptor expression. In fact, breast cancers that are only weakly hormone receptor-positive with <10% ER e...

Yes, particularly if the other clinical elements are appropriate for a luminal tumor - bone-dominant, low visceral burden, asymptomatic. I'd differentiate borderline (positive but < 10%) from more clearly HR+ tumors, and worry more about borderline ones than a tumor that is clearly by ASCO/CAP guide...

It is not just the level of ER-positivity, but other factors like patient age, co-morbid condition, number and sites of disease, number of lesions, symptoms, and level of symptoms that I take into consideration. Unless an immediate response is needed, I lean toward a combination of anastrozole and f...