“Who is an extraordinary human being, gracious, a consummate professional, a gentleman, a kind soul?

Final Answer: #AlexTrebek.”

So writes former Jeopardy! contestant Ana Navarro-Cárdenas on Twitter, reacting to the news that longtime—and universally beloved—Jeopardy! host Alex Trebek has Stage 4 pancreatic cancer.

Trebek, who has hosted Jeopardy! since 1984, revealed his diagnosis in a video posted on Wednesday, March 6, employing his characteristic deadpan accuracy, upbeat spirit and sly humor. While acknowledging that the prognosis for Stage 4 pancreatic cancer is “not very encouraging,” he vowed that “I’m going to fight this, and I’m going to keep working. And with the love and support of my family and friends, and with the help of your prayers also, I plan to beat the low survival rate statistics for this disease.“ Then he added, ”Truth told, I have to! Because under the terms of my contract, I have to host Jeopardy! for three more years! So help me. Keep the faith and we’ll win. We’ll get it done."

Tributes and well wishes have been pouring in on Twitter and other social media outlets from celebrities including Cher, Mr. T, Meghan McCain, Ken Jeong, Pat Sajak and Dr. Phil. Ryan Seacrest tweeted, “Alex Trebek—you are one of the greatest leaders and class acts in show business. Your level of grace, even in the face of adversity, is admirable and second to none. Stay strong and keep the faith, Alex. We are with you all the way!”

One of the most poignant tweets came from Ken Jennings, who has appeared on Jeopardy! more than any other contestant and has taken home the most winnings: “Trebek is in a way the last Cronkite: authoritative, reassuring TV voice you hear every night, almost to the point of ritual.“ Then, he added, “One thing I know for a fact: Alex is very aware of how much he means to millions of people, and how we will be pulling for him...I hope that’s a comfort.”

Click here to learn more about Jeopardy!

To learn more about pancreatic cancer, click on:

Pancreatic Cancer Basics

How to Navigate Pancreatic Cancer Resources

After Diagnosis, Finding Your “New Normal”

Pancreatic Cancer Action Network blog