my case...DCIS in right breast in 2007 and idc in left breast in 2018.... lumpectomies with radiation both times...tamoxifen the first time...anastrozole the second time. I think I am wondering if you have had bilateral mastectomy, then why do you need radiation at all? In my cases, I was told that the radiation should take care of any cancer cells left in the breast. If you have had both breasts removed, then there should not be a need for radiation. The chances of stray cancer cells is minimal. After genetic testing following the second cancer, I found that I have the CHEK2 genetic mutation. I just had a bilateral mastectomy with reconstruction. I was told that this should prevent me getting BC again. There was damage to both breasts caused by the radiation. Who knows what else has been damaged? I think if I had your history, was 77 and was taking tamoxifen, I would pass on the radiation. My cousin has had bilateral breast cancer with mastectomy both times and has passed on having radiation and is not taking aramatose inhibitors and she has not had a problem. Who knows what is the right thing to do. Everyone is different and every case is different.