Writing in the Sunday Times, the columnist, who was married to Home Secretary Amber Rudd during the 1990s, said: :I've got an embarrassment of cancer, the full English.
"There is barely a morsel of offal that is not included. I have a trucker's gut-buster, gimpy, malevolent, meaty malignancy."
The prognosis is currently uncertain.
Chemotherapy has shrunk some of his tumours and his doctors at Charing Cross Hospital are planning to try a new experimental drug.
In an interview with the Sunday Times, the journalist - whose brother Nick, a Michelin-starred chef, went missing in 1998 and hasn't been heard of since - said he had no regrets about the diagnosis.
He said: "I realise I don't have a bucket list; I don't feel I've been cheated of anything.
"I'd like to have gone to Timbuktu, and there are places I will be sorry not to see again.
"But actually, because of the nature of my life and the nature of what happened to me in my early life - my addiction, I know I have been very lucky.
"I gave up [alcohol] when I was still quite young, so it was like being offered the next life. It was the real Willy Wonka golden ticket, I got a really good deal.
"And at the last minute I found something I could do. Somebody said: why don't you watch television, eat good food and travel and then write about it? And, as lives go, that's pretty good."
The 62-year-old, who has four children, Flora, Alasdair, (from his marriage to Ms Rudd), and Isaac Mungo and Edith Lara, (from his current relationship) revealed his joy at his partner accepting his wedding proposal.
"I was so unprepared for how fantastically elated I felt", he said.
"After 23 years I really felt as if I was 16."
Reflecting on his illness, he added: "It's far tougher for Nicola than it is for me."
