Colorectal cancer: how bis is the problem, why prevent it, and how might it present?

Time trends In some developed countries, notably tn the United States. both the incidence and mortality rates for colorectal cancer have been stable and even declining.4 Declining incidence rates may reflect the preventive effects of a change in lifestyle as well as earlier cletection and treatment of adenomatous polyps and non-invasive cancers, before they advance to metastatic carcinomas. Declining mortality rates are felt to reflect both t he decreasing incidence of disease and the earlier detection of treatable disease. In the US population, tile greatest reduction in incidence and mortality has occurred in white women (Figure 1.5). But, in t he corresponding period, there was actually an increased mortality in African-American men of 21% and women of 7%.2