Recommendations from the American Cancer Society regarding follow up colonoscopies for people who have had abnormal polyps have had a standard of three years for follow up.  Some doctors now want to change that time frame to five years in order to make room for people to have colonoscopies who are in a higher risk category such as older patients who have never been screened.

In the study supporting the new claims researchers from the German Cancer Research Center found that having risky polyps taken out were 60% less likely to be diagnosed with colon cancer than people who had never been screened.

Read more: http://www.reuters.com/article/2012/07/24/us-colon-cancer-idUSBRE86N18020120724