There are several genes associated with cancer of the colon and rectum, which singly or in combination can double or even quadruple the chance of getting the disease. Regular screening for people over the age of 50 can reduce the rate of death of colorectal cancers by one third. If the tests were offered to the whole population, the costs would be substantial -- one estimate has put the cost of each prevented death at about US$200,000. Against that must be set the considerable cost, both social and financial, of treating people with incurable bowel cancers.
A project in the Fyn region of Denmark began in 1985 and involved 140,000 people. Some had regular screening tests every two years, while others acted as controls. Mortality from bowel cancer was cut by 18%. A similar project in Nottingham, England, enrolled 153,000 people and cut morality by 15%. However the number of lives saved was smaller than has been reported from America, where mortality has been cut by 30% or more. Part of the explanation is that many of the people who signed up for screening stopped having the test after a few years. In the Nottingham study, nearly two-thirds of te participants dropped out, while in Fyn the rate was about half of the total.
2. Early detection of colon cancer allows the doctor and patient to work together to gain control over the suffering caused by such an illness. Publicity about this disease may make some fidget with discomfort, but that's nothing compared with the effects of a diseased colon left untreated.
2. A colonoscopy is not innocuous. It can be complicated by severe intestinal bleeding, rupture of the bowel and, in rare instances, death. Colonoscopes are difficult to clean, and transmission of infection from one individual to another is well documented. Society as a whole suffers not only from the huge financial burden of an extensive screening programme but also from an ever increasing obsession with health, which, paradoxically, decreases our sense of wellness.