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

Tech Insider : Business
Katelyn Jonozzo
Katelyn Jonozzo, 31, had no symptoms of colon cancer and regularly ran marathons.

Katelyn Jonozzo

I have stage 4 colon cancer. I'm leaving my kids handwritten cards for their milestones, like birthdays and weddings.

Tech Insider : Business
A woman holding a greeting card
Lauren Gilbert and some of the cards in which she will write heartfelt messages.

Courtesy of Lauren Gilbert

A 36-year-old woman was told she was 'too young' to have colon cancer. Months later, she was diagnosed with stage 4.

Tech Insider : Business
Amber Kissell
Amber Kissell, 45, underwent chemotherapy for stage 4 colon cancer. Ultimately, she went into remission.

Amber Kissell

A 37-year-old nurse got unusually short of breath on a hike. She had stage 4 lung cancer.

Tech Insider
Close-up shot of Tiffany Job in a blue stripy dress.
Tiffany Job was diagnosed with stage four lung cancer at 37 years old, despite never smoking.

Captured by KLC

This ultrarunner was diagnosed with cancer 2 years ago, but didn't let it stop him. This summer, he'll run over 100 miles through Death Valley.

Tech Insider
A side-by-side composite image: on the left, a close-up of runner's shoes on a desert road; on the right, a photo of ultrarunner Ray Zahab
Ray Zahab is the perfect example of an endurance athlete.

Getty Images; Photo courtesy of Jon Golden; BI

Subscribe to chemotherapy