IBD-related carcinoma and lymphoma.

Patients with inflammatory bowel disease (IBD) have an increased risk of developing colorectal cancer (CRC). Risk factors are extent and severity of colonic inflammation, concurrent primary sclerosing cholangitis, and a positive family history of sporadic CRC. The chromosomal instability, microsatellite instability and hypermethylation pathways form the molecular background of IBD-related carcinogenesis, which is not different from sporadic CRC. The dysplasia-carcinoma sequence of IBD-related colorectal carcinogenesis makes patients suitable for endoscopic surveillance. In the future, new molecular biomarkers and endoscopic techniques may improve early detection of precursor lesions of IBD-related CRC. The potential of aminosalicylates and ursodeoxycholic acid as chemopreventive agents needs to be studied in randomized clinical trials. Patients with IBD who are being treated with thiopurines have a slightly increased risk of developing lymphoproliferative disorders, whereas patients with small bowel Crohn's disease have a high relative risk and a small absolute risk of developing small bowel adenocarcinoma.