A 31-year-old marathon runner thought she had norovirus. He was diagnosed with stage 3 colon cancer.

• Caitlin Jonozzo, 31, lived a very active lifestyle and had no symptoms of colon cancer.

• She was diagnosed in February when she suddenly felt severe pain and excessive swelling.

• Jonozo needed an emergency colostomy and was adjusted to running with a colostomy bag.

From a young age, Caitlin Jonojo prided herself on being very active.

Until the age of 18, she practiced gymnastics 4 to 5 days a week. “I loved discipline, I loved a regimented schedule,” Jonozzo, 31, told Business Insider. “It shows how important health and fitness is to your lifestyle.”

In her 20s, she gravitated toward marathon running. A supply chain analyst, Jonojo regularly wakes up at 4 or 5 a.m. to run for two hours before going to work. In 2024, she qualified to run the Boston Marathon. He couldn’t wait to run it in 2025.

That was before he felt sudden, intense stomach pains in February.

Jonozo started experiencing flu-like symptoms and began to get high. She chalked it up to norovirus, which was circulating in her Cleveland suburb at the time.

“My stomach started to really swell up — I almost looked like I was pregnant,” Jonozo said. “But that was also a symptom of norovirus, so I chalked it up to that.”

When the pain worsened — a stabbing sensation in her side and persistent vomiting — her two best friends urged her to go to the ER instead of waiting the next day. Jonozzo complied, assuming the worst-case scenario was appendicitis.

After emergency surgery to remove part of his colon, he learned he had stage 3 colon cancer, with secondary cancer in his stomach.

Jonojo said her training mindset helped her navigate her new reality. “I’m definitely a tunnel-vision person,” she said. “I think I cried for about 30 seconds. Then, I looked back at the doctor, and I was like, ‘What’s the plan? What do we do?'”

Zero warning signal

Jonozzo said she initially went to the hospital and was told she might have stomach pains or gas. He emphasized that he has a high pain tolerance and doesn’t come in unless it’s severe.

Eventually, he had an MRI, which revealed a three-inch tumor in his colon—one that was about to burst.

Within the next 48 hours, she had an emergency colostomy that removed a third of her colon and installed a colostomy bag. “I was in so much shock and so much was happening that I didn’t know what was going on,” she said.

After recovering from a catatonic state for 10 days, he learned his correct diagnosis. His doctor assumed the tumor had been growing for about a decade, Jonozzo recalled.

“How am I running a marathon?” she said. “How am I doing when I have a tumor in my stomach?”

Working with a colostomy bag

Weeks after surgery, Jonojo began her chemotherapy treatment. At first, she remained positive: poster boards with affirmations to leave around her house.

“It still didn’t really sink in, the journey I was about to go through, until I was about three or four rounds of chemo,” she said.

At that point, she started losing her hair and taste, experiencing skin changes, and developing neuropathy, losing sensation in her hands and feet. “That’s when I realized, ‘OK, you have cancer. It’s not just something we’re going to hang our heads over.’

A challenge was working. During treatment, her normal routine was out of the question. “I definitely had to tone everything down,” she said. He swapped long training runs and weightlifting for outdoor walks and three-mile jogs.

The biggest hurdle was the colostomy bag. “I was very self-conscious about the bag at first,” she said. But as she began connecting with other young cancer patients through The Gathering Place support group and the Colorectal Cancer Alliance, she began to embrace the bag.

“I’d go to the pool in a bathing suit, with the bag out, or I’d lift my shirt up at the gym and let people know the bag was there, which gave me a confidence boost,” she said.

Finding the positive helped her continue her normal routine as much as possible. “I think it’s amazing that they figured out how to get your bowels out and you can still go to the bathroom,” she said. “It’s a great contraption, if you ask me.”

He is running a marathon with his cancer support group

After seven months of treatment, Jonojo was declared cancer free. She finished chemotherapy in August and had a colostomy reversal in November. In mid-December, her first screening after treatment, she will learn more about her future screening schedule, which she already knows will include two colonoscopies a year.

She will officially be free to work out after her surgery – and is looking forward to getting back to her old routine.

“I’m a little nervous because normally I can pop out and run and do those things, but I have to take baby steps back into this,” she said. She plans to run three marathons in 2026, with the hope of re-qualifying for Boston through one of them.

She is especially excited for the Cleveland Marathon in May. She will run it as a team captain for her cancer fundraising group, which she says has given her a new passion. “I love advocating, I love talking to people,” she said. “I’ve always loved doing that – I never had the confidence to do that before.”

It’s just one way that her cancer experience changed her, she said, in addition to being more present.

“People think I’m crazy for saying this, but I really believe it’s one of the best things that ever happened to me,” she said. “I wouldn’t trade this experience for anything. I really wouldn’t.”

Read the original article on Business Insider