Despite being the picture of health and never having smoked a single cigarette, a 45-year-old father-of-two from Utah learned he has terminal lung cancer and a 5% chance of living over five years.

In 2023, after Chad Dunbar had completed an intense cycling journey where he logged over 3,000 miles in the mountains, he started experiencing pain and swelling in one of his calves.

Though he initially suspected the discomfort was from overworking his muscles during his gruelling ride, he had it checked out.

“The nurse came in…she’s like, hey, we think you have lung cancer. Man, there’s no way – no way I’ve got lung cancer. I was doing 3000 miles on my mountain bike every season and my lungs are probably the healthiest piece of me,” Dunbar said in a moving video where he shares his journey after he was handed a life-shattering diagnosis of terminal lung cancer.

Describing his reaction, the father of two shared, “It was surreal. It was denial. It was pissed off…Get mad… How? Why?”

‘Never a smoker’

His family members were equally puzzled, mostly since Dunbar, a “legit athlete” had never smoked.

“NO, he was never a smoker. He didn’t work in a mine. He’s lived in clean-air Colorado and Utah,” his brother-in-law, Jordan Reynolds, writes in a Facebook post. “Chad was in the best shape of his life when the Stage 3 [now stage 4] lung cancer showed up at age 45. He was a legit athlete.”

Leading cause of lung cancer

According to the Centers for Disease Control (CDC), cigarette smoking is the number one risk factor for lung cancer.

“In the United States, cigarette smoking is linked to about 80% to 90% of lung cancer deaths,” the CDC explains. “People who smoke cigarettes are 15 to 30 times more likely to get lung cancer or die from lung cancer than people who do not smoke.”

RET

After extensive testing, Dunbar was told that his cancer stemmed from a RET (rearranged during transfection) gene mutation, a rare but aggressive genetic change that can cause lung cancer in non-smokers. This type of cancer grows quickly and often spreads before it’s detected.

In Dunbar’s case, it was already widespread by the time it was caught.

Doctors soon confirmed that the cancer had already spread to his brain, liver, bones, and lymph nodes near his heart – a diagnosis of late-stage, metastatic lung cancer.

‘Feeling good’

After his shocking diagnosis, Dunbar initially responded well to an aggressive treatment plan. Doctors prescribed a combination of targeted therapies – designed to attack cancer cells carrying the RET mutation – along with standard chemotherapy, the Daily Mail reports.

And, for a while, it looked like the tide was turning.

“Big Improvement,” Dunbar said about his scans in the summer of 2023. “I had six spots in my brain that went down, three spots of my ribs they couldn’t find, spots of my liver had gone down, and the main tumor in my lung had continued to shrink.

“I’m thinking man, I’m feeling good.”

‘Ill take those odds’

But RET-positive lung cancer can be unpredictable, relentless, and incredibly difficult to treat long-term.

In an update clip shared in March 2024, Dunbar said recent scans revealed “a passenger mutation” that developed in his brain and liver. “My doctors gave me a 5% chance living over five years,” he said.

After allowing himself a “pity party,” he decided to fight and “enjoy every minute” he has with his sons Walker and Noah, and wife Allyson.

Dunbar adds, “Hey, you know what? Freaking 5%, I’ll take those odds. Every day is a battle. Hang on for one more day.”

Did you know about RET-positive lung cancer? Please let us know your thoughts and then share this story so others will know the lesser-known symptoms, like swelling and pain in the limbs.