Colorectal cancer genetic factors

Besides age, the development of colorectal cancer appears to be caused by variety of dietary or environmental factors, comor-bid disease states, and genetic susceptibility to the disease. Table 88-1 lists well-known risk factors for developing colon cancer. Epidemiologic studies of worldwide incidence of colorectal... 

In summary, the true association between most dietary factors and the risk of colon cancer is unclear. The protective effects of fiber, calcium, and a diet low in fat are not completely known. Lifestyle factors such as NSAID use and hormone use appear to decrease the risk of colorectal cancer, whereas physical inactivity, alcohol use, and smoking appear to increase the risk of colon cancer. Clinical risk factors and genetic mutations are well-known risks for colon cancer. 

Multiple factors are associated with the development of colorectal cancer, including acquired and inherited genetic susceptibility, environmental elements, and lifestyle choices. Overall, about 37% of... 

Numerous studies suggest that the development of colorectal cancer can be caused or promoted by dietary or environmental factors that affect the bowel, lifestyle choices, and certain comorbid conditions, in addition to physical and genetic susceptibilities. 

Incidence rates of colorectal cancer are high in all economically developed countries and are increasing (Boyle and Langman, 2000). Both genetic and environmental factors... 

Although folate is widely distributed in foods, dietary deficiency is not uncommon, and a number of commonly used drugs can cause folate depletion. Marginal folate status is a factor in the development of neural tube defects and supplements of 400 fj,g per day periconceptually reduce the incidence of neural tube defects significantly. High intakes of folate lower the plasma concentration of homocysteine in people genetically at risk of hyperhomo-cysteinemia and may reduce the risk of cardiovascular disease, although as yet there is no evidence from intervention studies. There is also evidence that low folate status is associated with increased risk of colorectal and other cancers and that folate may be protective. Mandatory enrichment of cereal products with folic acid has been introduced in the United States and other countries, and considered in others. 

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