Mr Limbaugh told listeners to his show that recent scans showed that the stage four cancer had continued to progress.
“It's not dramatic, but it is the wrong direction,”said Limbaugh.
“Stage four is, as they say, terminal,”
Mr Limbaugh added that he was surprised to have survived the cancer until October after getting the initial diagnosis.
The host said that he had been through a number of treatments, the third of which had showed some positive results until he got his last scan back.
Mr Limbaugh said he intends to continue his show, despite the impact of the cancer and his treatment.
"I am extremely grateful to be able to come here to the studio and to maintain as much normalcy as possible," he said.
He also explained to his audience why he had not given them more detailed on-air information on his illness before.
“In a nutshell, there are lots of ups and downs in this particular illness. And it can feel like a roller coaster at times that you can't get off of,” he said.
“And again, I want to stress here that I know countless numbers of you are experiencing the same thing. If it isn't lung cancer, it's some kind of cancer.
“If it isn't you, it's somebody really close to you. If it isn't an illness, it's something."
"We're all going through challenges. Mine are no better and mine are no different and mine are no more special than anybody else. But it can feel like a roller coaster.”
Mr Limbaugh was awarded the Presidential Medal of Freedom from Donald Trump in February the day after initially revealing his cancer diagnosis.