ER? HER? What do all the numbers mean?

Hey, sorry to hear this is your 2nd time going through this ! ER 7 and PR 8 stand for oestrogen and progesterone receptive! 7 and 8 is the scale it is measured on. 8 being the highest. Basically your cancer feeds off hormones. I was told this was a good thing as it’s very treatable. HER2 refers to a protein that can make the cancer grow and spread faster. It also means that it will be treated with specific drugs that target the HER2 protein. Depending if it is HER2 positive or negative. I hope that makes sense. It was how it was explained to me.
My breast cancer is ER 7 and PR 8 HER2 neg.  I’ve had a mastectomy and I start chemo on Friday. I’ll follow this with radiotherapy and hormone therapy. 
best of luck in your journey.