(CNN) Even as he battles pancreatic cancer, Alex Trebek still has his sense of humor.
"I've got stage 4 cancer, okay," the "Jeopardy!" host joked to CBS Sunday Morning. "Not stage 1, for sissies, that's just beginner's cancer. I've got advanced!"
Trebek, 78, sat down with Jane Pauley to talk about his illness.
In March, he posted a video on the show's official YouTube account announcing his diagnosis.
Alex Trebek announces he has stage 4 pancreatic cancer
Trebek didn't miss a day of work, even while undergoing chemotherapy.
'It wouldn't be right for me to walk away from this if I can possibly do it and I managed to do it," he said. "So what's the big deal?"
Constant pain in his stomach earlier this year led to testing which found a bulge in his stomach that he said was "the size of a small fist."
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Trebek said that early on in his treatment he suffered from excruciating pain both on and off camera while working on "Jeopardy!"
"I was on the floor writhing in pain. It went from a 3 to an 11," Trebek said. "And it happened three or four times that day while we were taping. So, that was a little rough on me."
He said he's been wearing a hairpiece to deal with the hair loss from chemotherapy.
Trebek credited his youthful appearance to having "Good genes."
"My mother passed away a couple of years ago at the age of 95," he said. "So, if I have a majority of her genes, I should be okay for a while."