Hi @margaretb
So glad you're educating yourself. I agree that knowledge is power. My original BC was stage 1, ER+ PR+ HER2-, BRCA2+ Ki-67 17% had a double mastectomy as only treatment. Surgeon told me 3-5% chance of recurrence, onco said < 1%. Seven years later, I had a BC tumor in my chest wall and into the pectoral muscle, but not into the bone. My BC is very aggressive this time Ki-67 50%. I had the tumor removed, but there was a positive margin in the pectoral muscle on the sternum side. Tumor was at about 1:00 position right side.

They did 37 radiation treatments on the right side of my chest, about a 8" x 12" area starting at the sternum and wrapping around my side. The last 9 treatments were boost treatments where they concentrated on the tumor area due to positive margin. It wasn't fun toward the end, but didn't seem to do any damage to my lungs. Skin healed. No lasting effects I'm aware of. Chemo is not on the table for me due to pre-x neuropathy and my oncologist doesn't think it would be effective against my cancer's personality anyway. I have been on Kisqali and Letrozole for 2.5 years since the radiation therapy was complete and so far so good. Side effects, but worth it to me.

I was concerned about my lungs with radiation too and they told me the new radiation therapy machines are so targeted that even the depth is well controlled so they did not expect the radiation to reach my lungs. If you move forward with RT, I would want to know if the radiation equipment at your facility is state-of-the-art. Prayers for you.