http://www.webmd.com/breast-cancer/guide/preventive-mastectomy
My grandmother died from breast cancer. If this was an option back then, she would have done it. And, no, it is not BS. There are women in their early 20s who are opting for this as a matter of survival.
A woman having her breasts removed YEARS and even DECADES before she MIGHT develop breast cancer is NOT a “matter of survival”.
Our neighbor across the street lost her mother to breast cancer about one year ago. She had tests done several weeks ago and there was a 90% chance she was carrying the same gene and would develop breast cancer. She is in the hospital this week getting double mastectomy.