The E! News host announced that doctors had discovered early stages of breast cancer during an appearance on NBC's Today on Monday.
Rancic, 36, told co-anchor Ann Curry that the cancer had been found after her doctor convinced her to undergo a mammogram before beginning a third round of IVF treatment in her bid to start a family with husband Bill Rancic.
Speaking to E! News co-host Ryan Seacrest on E! News later that day, she said: "Right before I went [on air] I was such a nervous wreck, you couldn't even imagine. I was shaking and Ann Curry gave me tissues right before we started and said to keep them under my dress just in case.
"I was thinking, 'Oh my God, I'm just going to be bawling all the time and I'll look too sad'. Then I realised I didn't want people to feel sorry for me."
Watch more of Giuliana Rancic talking to Ryan Seacrest below:
Rancic, who chose to make her diagnosis public in order to raise awareness of the illness and the need for women to undergo mammograms, went on to say that it was words of comfort from her husband that gave her the strength to continue with the interview.
"He came over and said, 'Just be yourself, tell your story and help women, show that you're a positive role model, that you're strong and you're getting through this. Don't cry'. He was such an amazing support at the last minute.
"Something about the words he said made me think, 'I have to do this for everybody else. I have to show these young women, especially, out there that you can find this early and be strong and proactive and that's what I'm trying to do'."
Rancic added: "I am going to survive, I'm going to be just fine, I'm not broken and that's because I found it early."
Bill took to his Twitter account following his wife's announcement to thank fans for their support and tell them that she had been reading their messages: "Thank you for all ur love & support today. G is reading all your messages. She will win this fight, I PROMISE, & be back better than ever! (sic)"
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