Andrew T. Chan, MD, MPH (Damon Runyon Clinical Investigator ‘08-‘13) of Massachusetts General Hospital, Boston, and colleagues at the Harvard School of Public Health reported the results of a large, long-term study demonstrating that 40% of all colorectal cancers could be prevented through regular colonoscopy screening. The new research also supports existing guidelines recommending that people with an average risk of colorectal cancer should have a colonoscopy every 10 years. The study was published in the New England Journal of Medicine.