Longtime “Jeopardy!” host Alex Trebek has been diagnosed with stage 4 pancreatic cancer.

The diagnosis was revealed by Trebek, 78, in a Wednesday YouTube video.

“Now, normally, the prognosis for this is not very encouraging, but I’m going to fight this, and I’m going to keep working,” he said. “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.”

Trebek has hosted “Jeopardy!” since 1984.

The reactions online to his cancer diagnosis showed what a beloved and essential part of American culture the game show host has become over the decades.

Check out some of the heartwarming comments below:

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