What % ER pos warrants Tamoxifen use

[mts]

Hi All,

I am 10% ER+ and PR- I am also on Tamoxifen. I'm still peri-menopausal too.
Does anyone know what base percentage "negativity" one needs to be in order to need Tamoxifen? The onc said something about the benefit of Tamoxifen -even in very low ER+ patients. But the benefits are so miniscule, that I wonder if its really worth taking the Tamoxifen with such low ER.
I hear now that many women opt to not take Tamoxifen with ER+ much higher than mine. I want to feel normal and the Tamoxifen as well as the Effexor I take to counteract the Tamoxifen side effects are driving me crazy.
I took Herceptin for a year after dose dense AC+T and radiation. Stage I, neg nodes.
What do you all think?

Maria (MTS)