A 39-year-old man had blood in his poop. He had colon cancer.

Blood in the toilet is among the most common signs of early-onset colon cancer, followed by abdominal pain and changes in bowel habits. It was the only symptom a man in his 30s had of the disease. Blood in the toilet is among the most common signs of early-onset colon cancer, followed by abdominal pain and changes in bowel habits. It was the only symptom a man in his 30s had of the disease.