Hi
I am ER+ PR+ (90%) and HER2 -, I had clear margins in the surgery, and no cancer in the lymph nodes. Pathology rated tumor as Grade 2. these were all great results. except when I saw the oncologist - I had a high Ki67 which to her meant my tumour was aggressive (it means it was a "Proliferative" tumor according to my oncologist) and acting as an aggressive tumour. So she recommended that I have chemo, which I had my last dose last week. It is about prevention.
I think you do need to wait for surgery pathology as they will test the whole tumour, not just a small part of it.
not sure if that helps you, you should be guided by your team. but thats my story.
Marg xx