**Part 4**

**The Colon** 

192 Gastrointestinal Endoscopy

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[42] Ishii, M.; Manabe, N. & Kusunoki, H. (2008). Real-time evaluation of dyspeptic

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involvement in acute visceral pain in rats. *Gastroenterol.* 134: 1094–1103. [39] Ugawa, S.; Ueda, T. & Ishida, Y. (2002). Amiloride-blockable acid-sensing ion channels

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on the safety and tolerability of transnasal esophagogastroduodenoscopy.

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**14** 

*Spain* 

**The Role of Colonoscopy in the** 

David Martínez Ares and Pamela Estévez Boullosa

**Prevention of Colon and Rectal Cancer** 

*Gastroenterology Unit. Complejo Hospitalario Universitario de Vigo, Vigo-Pontevedra* 

Colorectal cancer (CRC) is one of the most common tumors in our society. It is the most common gastrointestinal tumor and it is also estimated that between 5 and 6% of the population will suffer this tumor along their lives. Colorectal cancer is a tumor in which it is possible to perform primary and secondary prevention. It ranks second in frequency in both men and women, and it represents the second leading cause of cancer-related deaths in both men (after lung cancer) and women (after breast cancer). Indeed, CRC is responsible for 12% of cancer-related deaths in men and for 15% in women. It represents, therefore, a public health problem of first magnitude, causing over 10,500 annual deaths in Spain; so it is well established and cost effectiveness to use a program for early detection and prevention of this disease. CRC mortality in 2006 was almost double that the one recorded in Spain in 1975 in both sexes, considering them separately, and in the entire population as a whole. In relation to the rest of the Europe, Spain has an intermediate CRC mortality, lower than that recorded in Czech Republic or Slovakia, and well above from CRC mortality in Finland or Cyprus. In Spain, cancer mortality is higher in the north than in the south, and this difference is more significant in males. Furthermore, cancer mortality in the whole country is quite stable since

the beginning of this century, observing a slight increase in northern regions.

considerably improve the prognosis of this disease.

The survival of patients diagnosed with CRC is approximately 54% at 5 years after diagnosis. However, survival is significantly lower in the group of patients in advanced stages, and much higher, with a survival rate around 90%, when it comes to patients in early stages. Therefore, an early diagnosis of colorectal cancer can lead to a significant reduction in cancer mortality. Consequently, a program of screening or early detection could

Colorectal cancer is a health problem that fulfills all the requirements that the World Health Organization requires to consider a cost-effective screening program for early detection of neoplasia: first it is a very common disease, representing a major public health problem; second it is a disease with a well-known natural history, fulfilling in most cases the adenoma-carcinoma sequence (Figure 1), and this natural history is long enough so it can be interrupted by various diagnostic and therapeutic strategies; thirdly, we have diagnostic methods with enough diagnostic accuracy and at reasonable cost; fourthly, there is an effective treatment and, finally, this approach seems to be cost-effective. However, these screening programs have been implemented in very few sites in the world, having to be reduced in many cases to opportunistic screening or, at best, reduced to population at

**1. Introduction** 
