Beloved "Jeopardy!" host Alex Trebek has been diagnosed with stage 4 pancreatic cancer.

Trebek, 78, was born in Sudbury, Ontario, Canada, and became a naturalized U.S. citizen in 1998. He signed on to host “Jeopardy!” in 1984 and has been the only person to be the face of the long-running syndicated game show, which is distributed by Inside Edition's parent company, CBS Television Distribution.

Last fall, Trebek signed a contract extension to host the show until 2022, when he will be 82.

On Wednesday afternoon, Trebek took to the "Jeopardy!" YouTube channel to announce his diagnosis.

In the video message, Trebek said he wanted the news about his health to come directly from him and wanted to be "open and transparent" with his viewers about his diagnosis. He said he received the news this week.

"Normally the prognosis for this is not very encouraging, but I am going to fight this and keep working," Trebek triumphantly declared.

After he shared the news, celebrities and fans voiced their support.

I’ve said this before but Alex Trebek is in a way the last Cronkite: authoritative, reassuring TV voice you hear every night, almost to the point of ritual. — Ken Jennings (@KenJennings) March 6, 2019

Sending all my love, thoughts and prayers to Alex Trebek.



You are my hero. ❤️❤️🙏🙏pic.twitter.com/CcXhVtqUT8 — Ken Jeong (@kenjeong) March 6, 2019

We are all pulling for Alex Trebek who just revealed he has stage 4 pancreatic cancer. He vows to fight this and to keep working. We're with you, Alex. — David Muir (@DavidMuir) March 6, 2019

Pancreatic cancer begins when the cells in the pancreas “grow out of control,” according to the American Cancer Society. The pancreas is a small gland that lies behind the stomach and in front of the spine.

Patrick Swayze, Steve Jobs and Luciano Pavarotti have all died of the disease. In 2009, Supreme Court Justice Ruth Bader Ginsburg was diagnosed with pancreatic cancer; she later beat it.

Trebek studied philosophy at the University of Ottawa but said he always had an interest in working in broadcast. In 1961, he started working for the CBC as an announcer. By 1963, he was hosting his own radio show. His big television break came in 1973, when he started hosting “The Wizard of Odds” game show for NBC. He then floated around as the host of various shows, including “Strategy,” “The $128,000 Question,” and “Battlestars,” to name a few.

For the last 35 years, Trebek's sharp wit as host of “Jeopardy!” has made him a fan favorite among all ages. In 2014, he entered the Guinness Book of World Records for Most Gameshow Episodes Hosted by the Same Presenter, overtaking Bob Barker’s run on “The Price Is Right.” Recently, the show has gained new life with episodes streaming on Netflix.

Trebek has been married twice, first to Elaine Trebek Kares, to whom he said “I do” in 1974. The couple divorced in 1981. He remarried in 1990 to Jean Currivan-Trebek, with whom he has two children.

The TV star is also known for his philanthropy, entertaining troops as part of a USO tour since 1995. In 2016, he donated $5 million to the University of Ottawa, establishing the Alex Trebek Forum for Dialogue, which helps expose students to different worldviews.

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