A 31-Year-Old Marathon Runner Had Stage 3 Colon Cancer, No Symptoms

From a young age, Katelyn Jonozzo took pride in being very active. Up until she was 18, she practiced gymnastics 4 to 5 days a week. "I loved the discipline, I loved having a regimented schedule," Jonozzo, 31, told Business Insider. "That instilled h... [5184 chars]