Alex Trebek has shared another update since announcing his cancer diagnosis, which he said had previously reached "undetectable" levels,

The "Jeopardy!" host told CTV News he "went all the way down to numbers that correspond with a normal human being without cancer."

“Then all of a sudden, it blew up and went 50 percent higher than when it was first diagnosed," he said. "Go figure."

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Trebek, 79, said he is back on chemo.

"We'll see if the numbers go down," he said. "And if they do... they can't keep doing it forever of course. They’ll have to find a new protocol or whatever to administer. We'll play it by ear and keep chugging along until we either win or lose."

The father of two shared that he does have moments of regret about coming forward with his stage 4 pancreatic cancer diagnosis. He revealed the news in March.

“A lot of people are coming to me and looking for help, reassurance -- and that’s tough.”

He added that it's hard “trying to be as optimistic as you can when the other person feels none of that … they feel only despair. And I don’t know if I was strong enough or intelligent enough to help alleviate that despair.”

The host said the chemo treatments and cancer have taken a toll on him, affecting his work. After treatment, he gets joint pain. His eyesight "gets messed up a little," he told CTV News.

He lost his hair in the last round of chemotherapy, but it started to grow back. Trebek said it's gone again, and he's wearing wigs.

"There are weaknesses I feel in my body but I can always suck it up when it comes to tape the show," he said.

Trebek, who credits his wife, Jean Currivan Trebek, for supporting him through his illness, said he will continue to do the show "as long as my skills don't diminish."

“I’m sure there are observant members of the television audience that notice also, but they’re forgiving,” he said. “But there will come a point when they (fans and producers) will no longer be able to say, ‘It’s OK.’”

For more on Trebek's update, go to CTVNews.