Trebek made his illness public last March and has shared his progress and setbacks.

The “Jeopardy!” host struck a resolute but realistic tone in discussing the disease, including the toll it took during last month’s taping of a prime-time special, “Jeopardy! The Greatest of All Time,” with top contestants Ken Jennings, Brad Rutter and James Holzhauer, The contest begins airing Tuesday on ABC.

Trebek recalled mentioning to a series producer that he was “struggling a bit” on stage, but was assured that nobody noticed.

“I said, ’Well, I noticed,” said the typically precise host, who has been part of “Jeopardy!” since 1984.

Rep. John Lewis. | Riccardo S. Savi/Getty Images for U.S. Postal Service

Trebek has had good days and bad while undergoing treatment, but his on-camera performance doesn’t falter, said Jennings, who first competed on the show 15 years ago.

“The chemo is rough, but he can always just turn it on,” Jennings said. “The music came on, the lights came on, he would just stride out there and nail that show like nobody else. It was exciting to see him doing so well and taking that diagnosis so bravely. To me, he’s the last of that kind of old-school broadcasters, and it’s such a pleasure to watch.”

Rutter, who first played on “Jeopardy!” nearly 20 years ago, said word of Trebek’s illness hit him “like a ton of bricks.”

He occasionally drops into the Los Angeles-area studio to watch tapings and marvels at the host’s perseverance.

“Every time I go back, he’s better than he was last time. Even with cancer, he’s still held up to that standard, which is just absolutely amazing,” Rutter said.

Such praise and attention can make Trebek uncomfortable.

“I don’t want to get too mushy. I got mushy when young Dhruv (contestant Dhruv Gaur) wrote his final ‘Jeopardy!’ response, ’We love you Alex! ’That caught me by surprise, brought me to the edge of tears,” he said of the moment that aired during November’s Tournament of Champions.

“It’s humbling to realize there are so many people out there who care enough about you to want to pray for you every day, who want to send you their best wishes,” he said. But Trebek said he never loses sight of the show’s real attraction.

“I tell people all the time, ’Hey, folks, the show’s not about me, it’s about the material and the contestants. Those are the two main items. And if they shine, if the material plays well, if the contestants do well, people will enjoy the show. If they enjoy the show, probably some of that enjoyment will rub off on their views of me, and they’ll like me too,” he said, modestly.

But he expressed confidence that it will thrive with someone new.

“No matter who’s hosting it, ‘Jeopardy!’ will go on. It’s a quality program and it’s put together by very bright people. And when I move on, that doesn’t matter, “ he said. ”It’s the best kind of reality television, so it will endure.”

