colon cancer prevention Measures taken to prevent the formation of colon cancer. Colorectal cancer can run in families. The risk of colon cancer is increased for a person whose immediate family member (parent, sibling, or child) had colorectal cancer. It is increased further for a person who has had more than one such relative with colorectal cancer or a family member who has developed colon cancer earlier than 55 years of age. Individuals to whom any of these circumstances apply should undergo colonoscopy every 3 years, starting at an age that is 7 to 10 years younger than when the youngest family member with colon cancer was diagnosed.
