Chronic Inflammatory Bowel Disease Risk Factors related to Colorectal Cancer

Patients with inflammatory bowel disease have an increasing risk for colorectal cancer which is believed to begin from no dysplasia progressing to indefinite dysplasia, low-grade dysplasia, high-grade dysplasia and finally to invasive adenocarcinoma, although colorectal cancer can arise without proceeding through each of these steps. As regards to the risk factors predisposing to colorectal cancer in the setting of inflammatory bowel disease, it seems that the risk increases with longer duration and greater anatomic extent of colitis, the degree of inflammation, and the presence of primary sclerosing cholangitis and family history of colorectal cancer. Concerning the mechanisms of carcinogenesis, it is now well established that the molecular alterations responsible for sporadic colorectal cancer, elucidated namely chromosomal instability, microsatellite instability, and hypermethylation, also play a role in colitis-associated colon carcinogenesis. Chemoprevention strategies include the management of medicaments such as aminosalicylates, ursodeoxycholic acid, and possibly folic acid, the exact role of which remains to be elucidated.Keywords: bowel disease, inflammation, patients, dysplasia, cytokines, cancer, smoking, chemoprevention, etc.