“This day has been one of the most difficult days in recent memory, for me, because I’ve known this moment was coming,” the conservative juggernaut said on his show. “I’m sure that you all know by now that I really don’t like talking about myself and I don’t like making things about me… one thing that I know, that has happened over the 31-plus years of this program is that there has been an incredible bond that had developed between all of you and me.
“So, I have to tell you something today that I wish I didn’t have to tell you," Limbaugh, 69, told his radio listeners. "It’s a struggle for me, because I had to inform my staff earlier today. I can’t help but feel that I’m letting everybody down. The upshot is that I have been diagnosed with advanced lung cancer.”
Many took to social media with heartfelt reactions to the announcement.
"Rush Limbaugh is a National Treasure who has made a difference on the airwaves of America for 30 years. Rush, Karen and I will be joining millions across this Country in praying for your swift recovery. God Bless You!" Vice President Mike Pence tweeted.
"My heart and prayers go out to Rush Limbaugh, who has been diagnosed with advanced lung cancer. He has inspired a generation to enter politics, including myself. We are fighting with you, Rush!!!" Trump campaign national secretary Kayleigh McEnany wrote.
"Prayers for Rush Limbaugh," Judicial Watch President Tom Fitton reacted.
"Prayers for my old friend Rush @Limbaugh," Media Research Center founder Brent Bozell tweeted.
"The news that Rush Limbaugh has lung cancer is horrible, but he's got millions of people behind him. He's a legend and a fighter. If you are the praying kind, do it," wrote Townhall senior columnist Kurt Schlichter.
Others expressed kind words about the conservative radio giant.
"If you currently or have ever worked in conservative media, you owe Rush a debt of gratitude. He's the founding father of this entire industry, and blazed the trail for the rest of us," radio host Steve Deace said.
Rush Limbaugh's announcement that he is battling advanced lung cancer is such sad news - I wish him a speedy recovery - will pray for him and his family. Love you Rush!" Fox News contributor Sara Carter tweeted.
"Rush Limbaugh just announced that he is battling advanced lung cancer. Praying for him during this difficult time. Fortunately, the man is a determined fighter filled with enormous strength & will power! Wishing you the best Rush!" wrote Rep. Lee Zeldin, R-N.Y.
"Pray for Rush and his family. Rush's impact on the conservative movement can't be overstated -- nearly every conservative of my generation grew up listening to him -- and that impact will be felt for decades to come," conservative commentator Ben Shapiro reacted.
"No one has done more to advance the cause of freedom than my friend, Rush Limbaugh. His brilliant analysis day after day, year after year represents a monumental contribution to conservative principles & a strong America. Our prayers are with him & his family for hope & healing," former Attorney General Jeff Sessions wrote.
The radio veteran -- one of the most powerful voices in conservative media -- said he “can’t describe” the feeling but he’s aware his audience understands him.
“The rest of the world may not,” Limbaugh said. “But I know that you do.”
Limbaugh called his listeners one of “the greatest sources of confidence” that he’s ever had in his life.
“I hope I will be talking about this as little as necessary in the coming days, but we’ve got a great bunch of doctors, a great team assembled, we’re at full speed ahead on this,” Limbaugh said. “It’s just now a matter of implementing what we are going to be told later this week.”
He said he “hopes” to be back on Thursday
“If not, it’ll be as soon as I can,” Limbaugh said. “Every day I’m not here, I’ll be thinking of you and missing you.”
Fox News' Brian Flood contributed to this report.