In an interview with Hello! magazine, Osbourne, 60, said:
As soon as I found out I had the breast cancer gene, I thought: 'The odds are not in my favour'.
I've had cancer before and I didn't want to live under that cloud: I decided to just take everything off, and had a double mastectomy.
More top news
Party rules state the new Tory leader will be announced on 9 September, but the way things are going it could all happen much sooner.
Contrary to Michael Gove's belief, people do need experts, now more than ever as we work out what leaving the EU actually means.
Cool and breezy for the time of year