In a post on social media, the 40-year-old wrote: “I believe I may have had the most surreal, mind-blowing, humbling five days of my life.
“I cannot thank you for your generosity at launching the @bowelbabefund [or] the Duke of Cambridge for going above and beyond to make a very special memory happen.
“Can’t quite believe I’m actually a Dame!
“My family are being amazing and as emotional as it all is, we are finding so much to smile about in the sadness.”
On Friday, Prince William, 39, presented a damehood to the You, Me and the Big C presenter for raising nearly £6million for Cancer Research UK in days.
Mum-of-two Dame Deborah revealed her “surreal” meeting with the Duke via her Instagram page.
She told her more than 630,000 followers how “kind” William “made everyone feel at ease”, adding that he is “welcome back any time”.
Dame Deborah was diagnosed with Stage 4 bowel cancer aged 35 in December 2016, and was given an eight per cent chance of living for five years.
She defied the odds time and time again but last summer the drugs that had been keeping her alive stopped working.
Her liver started to fail and, on Monday, the BBC podcast host shared an emotional Instagram post revealing she is now receiving end-of-life care at her parents’ home in Woking, Surrey. Donations flooded into her JustGiving Bowelbabe page – which topped £5.8million yesterday.
No10 confirmed that she was to be made a dame on Thursday night.
A spokesman said: “The Queen has been pleased to approve that the honour of damehood be conferred upon Deborah James.”
Prime Minister Boris Johnson said: “If ever an honour was richly deserved, this is it.
“Deborah has been an inspiration and her honesty, warmth and courage has been a source of strength to so many people.”