If not for his past heart attack and its follow-up maintenance, Larry King might not have learned about a lung tumor until it was too late.

In an interview with Extra's Mario Lopez, the veteran talk-show host says doctors noticed a Stage 1 lung tumor on his annual chest X-ray.

“It wasn’t really a battle," he explained. "I have a checkup every year. I’ve gone through a lot in my life — I’ve had a heart attack and heart surgery. Part of my checkup is the chest X-ray, and that is the protocol. I do it every year ... it was always normal. Then the doctor says, ‘I see a little spot here."

On July 17, the 83-year-old King underwent surgery at Cedars-Sinai in Los Angeles to remove what turned out to be a malignant, Stage 1 tumor.

“I had no clue at all," he said. "If I had not had the chest X-ray, it would have progressed.”

He added that he'll now get checkups every six months so doctors can monitor his lungs, which he has no doubt have suffered the effects of his long-term smoking habit.

"I smoked for 30 years. The day of the heart attack, I never smoked again, and I smoked three packs a day — I smoked in the shower ... Thirty years later, I said to the doctor, 'Is this connected with that?' Absolutely.”

Thanks to early detection, he was back at work on his Ora.TV talk show a week after his operation.

Now, he figures, “I’ll die on the air probably.'” But hopefully not from lung cancer.