Polyps
These are small benign growths like a wart or skin tag that occur on the lining to the bowel in 1 in 5 of us as we get older (over 55). A few of these (only a few) can develop, over 5-10 years, into cancers. So it is well worth finding them as it is now simple and safe to remove them
In theory most bowel cancers could be prevented by removal of these polyps, which would dramatically reduce the number of people having cancer.
As people tend stop forming them after the age of 65 the window of opportunity for removing them is between 55 to 65 years of age