She now has to have reconstructive surgery with implants, there are great dangers with that also, plus she has to maintain the false breasts every 10-15 years or less., they can rupture, connective tissue can shrink, they can be painful, silicone gel does not get absorbed by the body and if she uses saline, there is a deflation rate every year.
Vlad is correct, she has made this decision from a position of fear. Genetics are only one part of the puzzle. I had no gene probabilities with my breast cancer, still I developed it. There is scare mongering amongst the medical community. With right living and a more vegetarian or raw based diet, plenty of quality exercise and learning to cope with her 'stressful' life, she may well have never gotten breast cancer.
The stress on the body of having surgery can also cause problems now and in the future, this is a major surgery- then having foreign parts implanted in the body which need maintenance. All in all, I do hope that other women will not automatically follow her decision but think carefully of how they can improve their own ability to ward of cancer with right living, regardless of genes.