Distribution of polyps in the large bowel in relation to age. A colonoscopic study.

In a colonoscopic study of the anatomical distribution of 600 adenomas, polyps of all sizes in patients up to 55 years old were predominantly located distally. With advancing age of the patients a successively greater proportion of at first small and then also larger polyps was found in the intermediate and proximal parts of the colon. These findings support the assumption that polyps of the gut as a rule originate in the distal part of the large bowel, only later to appear proximally. This concept is important, since it might serve to explain conflicting experience with regard to the site of colorectal tumours.