Colon cancer is a disease in which malignant (cancer) cells form in the tissues of the colon. Health history affects the risk of developing colon cancer. Signs of colon cancer include blood in the stool or a change in bowel habits. Tests that examine the colon and rectum are used to diagnose colon cance

As far as screening for colon cancer goes, it really depends on your family history as to when you start screening for it. So, for example, if you have a mother, or a father, or a sibling that has been diagnosed with colon cancer, you really wanna start screening about ten years before their age of diagnosis.