Michael Douglas hopes to beat "intense" cancer

Michael Douglas speaks at the American Theatre Wing's 64th annual Tony Awards ceremony in New York in this June 13, 2010 file photograph.

LOS ANGELES (Reuters) - Michael Douglas said on Tuesday he felt optimistic about recovering from throat cancer but drew gasps when he told a television audience he had the most advanced stage.

The 65-year-old "Wall Street" actor told TV talk-show host David Letterman that a biopsy indicated that his cancer was at stage IV, which he described as "intense, and so they've got to go at it ..."

Letterman asked whether stage IV was a good diagnosis.

"Um no," Douglas replied, according to a transcript provided by CBS' "Late Show with David Letterman."

Stage IV cancer has spread far beyond the original tumor and is usually impossible to cure.

"No, you like to be down at stage I ... but it has not -- the big thing you're always worried about is it spreading ... and the expectations are good ...

"The percentages are very good," Douglas added. "I would hate to say, but right now, it looks like it should be 80 percent, and with certain hospitals and everything, it does improve."

According to the National Cancer Institute, patients with stage IV head and neck cancer usually undergo surgery, radiation and chemotherapy.

Douglas told Letterman that his cancer was caused by his drinking and smoking.

He said his throat had been bothering him for a while, and a multitude of doctors put him through a battery of tests in the early summer, but had found nothing.

After a summer break, he underwent a biopsy, which revealed his advanced cancer.

He expressed frustration with the doctors who could not find anything, "because I was on it early in the summer and started complaining about something, but they couldn't see it then."

Douglas is married to actress Catherine Zeta-Jones, with whom he has two children, Dylan, 10, and Carys, 7.

(Reporting by Dean Goodman, Editing by Eric Beech, Sandra Maler and Maggie Fox)