@joannemm34293 a high ER (and PR) means that aromatase inhibitors (or tamoxifen for pre-menopause) should have a high level of effectiveness. The scores make the cancer more treatable, in other words.

I asked the Breast Cancer Index people why extended treatment had no benefit for me, with those high ER and PR scores and a low Oncotype. They explained that the Oncotype looked at how many cars were in the road and they looked at the speed of the cars (or vice versa, I cannot remember).

I would think the BCI result would show that my cars were moving slowly but then I had a high risk of recurrence of 5.7% (they have since changed their labelling of risk).

It's hard to base our decisions on Oncotype, BCI and other testing but we don't have much choice. My bones needed attention or I might have continued another two years anyway. One oncologist said I could two more years anytime so once my bones are taken care of (almost done Tymlos) I might go back and ask about that. Letrozole would not be to treat but to prevent.