Colorectal cancer epidemiology

Carotenoids and urino-digestive cancers — On the whole, findings from epidemiological studies did not demonstrate a protective role of carotenoids against colorectal, gastric, and bladder cancers. Indeed, most prospective and case-control studies of colorectal cancer showed no association with dietary intake or plasma level of most carotenoids. - Only lycopene and lutein were shown to be protective against colorectal cancer. Otherwise, findings from the ATBC study s showed no effect of P-carotene supplementation on colorectal cancer. 

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... 

Epidemiology and Biology of Colorectal Cancer Adjuvant Therapy of Colon Carcinoma Adjuvant Therapy of Rectal Carcinoma Future Trends in Combined Modality Therapy for Colorectal Carcinoma References... 

In addition, very recent work indicates that COX-2 may play a vital role in the regulation of angiogenesis associated with neoplastic tumor cells, hence COX-2 inhibitors may block the growth of blood vessels into developing tumors (56). Thus, according to epidemiological, clinical, and experimental data, COX-2 appears to be intimately related to the development and growth of some types of cancer, especially of colorectal cancer. 

Martinez, M. E., and Willett, W. C. (1998). Calcium, vitamin D, and colorectal cancer A review of the epidemiologic evidence. Cancer Epidemiol. Biomarkers Prev. 7,163-168. 

Keating, J., Pater, P, Lolohea, S., Wickremesekera, K. (2003). The epidemiology of colorectal cancer what can we learn from the New Zealand Cancer Registry Journal of the New Zealand Medical Association 116, No 1174, www.nzma.org.nz/journal/116-1174. 

Aloe, senna, and cascara occur naturally in plants. These laxatives are poorly absorbed and after hydrolysis in the colon, produce a bowel movement in 6-12 hours when given orally and within 2 hours when given rectally. Chronic use leads to a characteristic brown pigmentation of the colon known as melanosis coli. There has been some concern that these agents may be carcinogenic, but epidemiologic studies do not suggest a relation to colorectal cancer. 

Dietary Fiber. There is no conclusive evidence to indicate that total dietary fiber exerts a protective effect against colorectal cancer in humans. Both epidemiological and laboratory reports suggest that if there is such an effect, specific components of fiber, rather than total fiber, are more likely to be responsible. 

The results of the feeding experiment of Kakiuchi and co-workers seem consistent with the picture in humans — mutations in AFC that result in a truncated protein and cancer The results of this rat study an relevant to epidemiological data regarding high-meat diets and colorectal cancer. 

The biochemical mechanisms that may have led to the C G T A mutation are discussed later. The mechanisms are consistent with epidemiological data suggesting that a low consumption of fruits and vegetables leads to an elevated risk for colorectal cancer. One might ask, "How can mutations involving CG T A, rather than other base changes, be associated with a diet low in fruits and vegetables " Possible answers are revealed in what follows. 

In an epidemiological study, chronic abusers of anthranoid laxatives (identified by the detection of pseudomelanosis coli) had an increased relative risk of 3.04 (95% Cl = 1.18, 4.90) for colorectal cancer (10). 

Epidemiology of Diet and Colon Cancer Epidemiological Study of Colorectal Adenomas... 

Le Marchand L, Hankin JH, Wilkens LR, et al. Dietary fiber and colorectal cancer risk. Epidemiology 1997 8 658-665. 

Wang, W Xue, S Ingles, S.A., Chen, Q Diep, A.T., Frankl, H.D., Stolz, A. and Haile, R.W. (2001) An association between genetic polymorphisms in the ileal sodium-dependent bile add transporter gene and the risk of colorectal adenomas. Cancer Epidemiology, Biomarkers el Prevention, 10 (9), 931-936. 

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