Karissa Rund was 14 when she ran from the shooters at Columbine High School.

Now 33, she's running from stage IV colon cancer, a race she's been trying to win for two years.

“I was diagnosed in November of 2015,” Rund said. “It was very sudden.”

Colon cancer is rare for someone Rund's age.

“It's very unusual for a 31-year-old to be diagnosed with colorectal cancer,” said one of Rund's doctors, Dr. Wells Massersmith, a Gastrointestinal Oncologist at UCHealth. “For the most part, this is a disease of elderly patients.”

He said there is no perfect, non-invasive affordable screening test that can help identify colon cancer in young people.

“I think that's really a key message is even if you're young, if you have things like weight loss, rectal bleeding a change in your bowel habits that's not explained or something just isn't right take that seriously,” he said. “And even if the first provider you see says, 'Oh don't worry about it, it's just hemorrhoids or something' and it keeps happening, you need to keep pressing and call them back and go see your doctor again and just tell them you're concerned about this.”

Rund's cancer has been aggressive. She's had several surgeries and chemotherapy but the cancer keeps coming back.

She's hoping a trial therapy in Philadelphia next year could teach her body to fight the cancer.

This is her last hope.

“The odds aren't good that I'm going to make it five years. They're about ten percent for most Stage IV colon cancer survivors,” she said. “I hope that I have a chance. Is this a short story? I hope it's not.”

Rund said her faith is helping keep hope alive.

“I feel God is there through all of that,” she said. “My faith tells me I'm here for a reason. I want to stay for so many reasons. I want to have children, a full life, and I want to tell people this story and tell them about the hope that I've had in God, about the hope that I find in Him.”

If you'd like to help donate to Rund's medical expenses, she has a GoFundMe page: http://bit.ly/2BncDRd.