Hi Ranveig,
This is a very difficult and personal decision. I know for me having both breasts removed was piece of mind and was the most I could do to prevent local recurrance. Avoiding radiation was also important for me because I wanted reconstruction and sometimes radiation can affect your choices.
Funnily enough I contributed to a story about this very thing. This is the link, it was published just yesterday.
http://www.health.ninemsn.com.au/healthnews/8748718/women-getting-healthy-breasts-removed-for-peace-of-mind
Good luck, Xxx Louie