CLEVELAND, Ohio (WJW) - South Euclid resident John Cardwell personifies the phrase "overcoming the odds."

At 15, he was diagnosed with ulcerative colitis, an autoimmune disease. He said the simplest tasks, like walking across a room, were extremely taxing on his body.

Fourteen years later, in 2019, he decided to take control of his life and had an elective surgery to have his colon removed.

Cardwell told FOX 8 News that a few weeks later, doctors discovered he had stage 2 colon cancer.

According to Cardwell, a surgeon told him he was one of his luckiest patients ever because it was detected.

He started chemotherapy. His final radiation treatment came in February of 2020. The cancer was gone, but it took four years of MRIs to confirm he was officially cancer-free.

Cardwell said he finally had something he'd never had in his life.

"For the first time in my life, I had a clean bill of health," he explained. "It was, it was relief."

Around that time, he started taking outdoor walks near his home. The walks got longer and longer.

Cardwell said that at some point last year, he decided to start running, with a goal of completing a 10K because it was something he'd never been able to do in his life.

Less than a year later, he completed the 10K, part of the Cleveland Marathon, on Saturday.

"I view it as a stepping stone. It's something to get me to where I want to be. So, I'm glad I did it," he said.

Cardwell hopes to do the half marathon next year. He said that he enjoys running and never views it as a hard task or a workout because it's something he was never able to do previously in his life.

He hopes his story will show others that you can overcome life's obstacles. He said the challenge is finding your way around them.

"I think the one piece of advice I'd give people is that it doesn't matter where you are now. It's where you want to be that matters," Cardwell said.