Kurt Gibson knows life is an amazing race. During his last semester of college, the 22-year-old ultimate Frisbee player began to notice that he was more fatigued than usual and had blood in his stool. “I was in peak physical shape, so I just figured this was the result of my active lifestyle,” says Kurt, who decided to ignore what would turn out to be colorectal cancer symptoms.

When the fatigue and blood didn’t go away, Kurt saw...