65-year-old actor Michael Douglas has told the world that he has Stage 4 throat cancer. On Tuesday night, Douglas appeared as a guest on the Late Show with David Letterman, and said that he will be undergoing surgery, radiation, and chemotherapy for the cancer that was discovered in early August.

Douglas reportedly was a very heavy smoker up until 2006 when he decided to give up the habit. He was smoking a half a pack of cigarettes daily, which likely contributed to his cancer. Throat cancer is more common in men who are over the age of 45, and up to 90 percent of all throat cancer cases are caused by smoking.

According to Michael Douglas, doctors have given him a very good prognosis on his illness. He was given an 80% chance of recovery even though it is a stage 4 tumor.

Douglas said, “I am very optimistic.”

He will certainly have the support of his wife, actress Catherine Zeta-Jones, as he is in for a long and tough battle.