**11. Primary prophylaxis of colorectal adenomatous polyps and CRC**

Colorectal cancer prevention is divided into three groups: primary, secondary and tertiary. Diet and lifestyle are considered as targets in primary CRC prevention, which includes

Protective role of calcium is confirmed in different trials. A result from a study claims that regular daily intake of 3 g calcium as supplement reduce the risk of colorectal adenomas relapse 1 year after their removal. This fact is an evidence of protective action of calcium in the early stages of colorectal carcinogenesis (Baron et al., 1999). Another study reported that high calcium intake is associated with vastly lower risk of development of distal CRC, but

The protective role of ursodeoxycholic acid for CRC is probably due to the reduced absorption of the secondary deoxycholic acid, which increases epithelial proliferation and promote carcinogenesis. A study proved that use of synthetic ursodeoxycholic acid is associated with reduced risk of development of CRC in patients with ulcerative colitis and primary sclerosing cholangitis (Peng et al., 1995). Other authors found that administration of ursodeoxycholic acid in patients with primary biliary cirrhosis, who have undergone polypectomy, is connected with vastly reduced risk of CRP relapse (Serfaty et al., 2003).

Abundant data for the role of selenium as a prophylactic substance for the CRC are constantly accumulating. Epidemiological studies have shown anticancer role of selenium since 1970. In some parts of Europe there is low amount of selenium in the soil and European population show tendency of lower intake of selenium in the last 25 years (Rayman, 2000). A lower risk for CRC was detected in persons who take 200 g selenium daily (Clark et al., 1996). Some authors found lower serum levels of selenium in patients

We can conclude that the choice of proper chemopreventive tool is difficult. Such a tool must be effective, cheap, safe and easy to use. It is calculated, that up to 80% of the cases with CRC could be prevented by alteration of diet habits (Cummings & Bingham, 1998). These data oblige us to fully clarify the role of chemoprevention in colorectal neoplasms. Combination of chemoprevention with screening endoscopy is of great importance for reduction of the CRC mortality. The most significant chemopreventive agents are the

The main indications for applying chemoprevention in our patients were: patients with adenomatous polyposis of large bowel; patients who have undergone endoscopic polypectomy; operated for CRC patients, IBD patients and patients with hereditary syndromes of CRC. 70 of our patients took chemopreventive agents: acetylsalicylic acid,

Colorectal cancer prevention is divided into three groups: primary, secondary and tertiary. Diet and lifestyle are considered as targets in primary CRC prevention, which includes

polyvitamins, folic acid, selenium, NSAID, calcium, 5-ASA, ursodeoxycholic acid.

**11. Primary prophylaxis of colorectal adenomatous polyps and CRC** 

acetylsalicylic acid and other NSAIDs, antioxidants, calcium and selenium.

**10.3 Calcium** 

**10.5 Selenium** 

not proximal CRC (Wu et al., 2002).

**10.4 Ursodeoxycholic acid** 

with CRC (Scieszka et al., 1997).

**10.6 Chemoprevention in our patients** 

modification of the established risk factors for colorectal polyps. These are: limitation of certain foods, beverages and habits; improved physical activity; consumption of protective foods; eradication of *H. pylori*. Important question is whether it is possible to apply primary prophylaxis in CRC and its precursor – adenomatous colorectal polyposis and if risk factors for CRC and CRP are avoidable and at what extent? Considering the growing epidemic of CRC this issue is waiting its prompt answer. What kind of healthy style of life we can offer to threatened people, similarly to the primary prevention in other diseases like cardiovascular disease, ischaemic heart disease and arterial hypertension, and distinct type of cancers? A great part of risk factors for CRC and CRP are associated with the diet, the lifestyle, exogenous carcinogens, some diseases and disease-like conditions. However, some protective factors for CRC and CRP are famous and could be recommended. As a primary prevention in healthy persons change of diet habits, reduction of body weight, refusal of tobacco smoking and alcohol intake are recommended. Preventive role of calcium, magnesium, β-carotene, vitamins, folic acid and selenium for CRC and CRP is still disputable. Acetylsalicylic acid and other NSAIDs for this purpose are not commonly used, because of their adverse side effects (Sandler, 2004). However, if new and convincing data are available, we can try to restrict influences of known risk factors and to cure precancerous conditions and will be able to perform proper primary prevention for CRC and colorectal adenomatous polyposis.
