Genetic predisposition reduces breast, ovarian cancer risk with preventive surgeries:

[News]

A long-term study of women with a genetic predisposition for breast or ovarian cancer showed that those who elected major preventive surgeries had a significantly reduced risk of those cancers.

More... (http://www.news-medical.net/news/20100904/Genetic-predisposition-reduces-breast-ovarian-cancer-risk-with-preventive-surgeries-Study.aspx)