I had a mastectomy. Two weeks later a lump on chest wall. Confirmed cancer. Chemo to shrink. Then a lumpectomy. The MRI said it was gone. They went in again based on MRI. Another 3.5 cm of cancer. Now 3 bad margins. The surgeon rationalized it could be “false positive margins” and go to radiation to clean up any remaining cancer. You would need to put a gun to my head to live with that. Thank God I pushed them ( two tumor boards later). Final surgery took out another 1.2 cm with finally clear margins. The motto of the story: MRI’s don’t necessarily pick up cancer. The only true way is a pathology report from surgery. Otherwise it is just guessing. Everyone in my case was guessing and they were wrong!