Dear OncoLink "Ask the Experts,"
I am at high risk for colon cancer because my mother had colon cancer at age 37, my maternal great aunt had colon cancer, and my father's mother died of colon cancer. My question is if someone is at high risk and has had a normal colonoscopy, how often after that should he or she considers having another colonoscopy?
Li Liu, MD, OncoLink Editorial Assistant, responds:
Thank you for your interest and question.
According to the American Cancer Society and the American Gastroenterological Association colorectal cancer screening guidelines, men and women over age of 50 not in a high-risk group (see below) should use the following guidelines:
*A digital rectal examination (DRE) should be performed at the time of each screening sigmoidoscopy, colonoscopy or barium enema examination. People are considered at high risk for colon cancer when they have any of the following risk factors:
- Yearly fecal occult blood test plus flexible sigmoidoscopy every 5 years*, or
- Colonoscopy every 10 years*, or
- Barium enema every 5-10 years*.
For those in a high-risk group, especially with a family history of colorectal cancer, the American Cancer Society and the American Gastroenterological Association recommend the above screenings at age 40 and a colonoscopy every 3-5 years thereafter.
- A strong family history of colorectal cancer or polyps (cancer or polyps in a first-degree relative younger than 60 or in two first-degree relatives of any age),
- Families with hereditary colorectal cancer syndromes (familial adenomatous polyposis and hereditary non-polyposis colon cancer),
- A personal history of colorectal cancer or adenomatous polyps, or
- A personal history of chronic inflammatory bowel disease.