The 60-year-old, who battled colon cancer in the early 2000s, was horrified to discover she has a genetic mutation which raises her chances of developing the disease, reported Hello! magazine.
"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," she said.
The reality TV star, whose son Jack became a first-time dad to daughter Pearl earlier this year, insists she had no doubts about undergoing the operation - which lasted 13 hours.
"For me, it wasn't a big decision, it was a no-brainer. I didn't want to live the rest of my life with that shadow hanging over me. I want to be around for a long time and be a grandmother to Pearl."