There’s a list of reasons many of us give as to why we don’t need a colonoscopy. I can’t take time off work. I heard the preparation is terrible. I don’t have any symptoms. That sounds embarrassing. Yet, the list of reasons why we do need one make all of those excuses seem trivial. Colon cancer is the third leading cause of cancer-related deaths among men and women in the United States. Colon cancer may not present with any symptoms.