Malaignant tumors arising in inflammatory bowel disease

Inflammatory bowel disease (IBD) patients have an increased risk for colorectal cancer (CRC). While not always appreciated, this is true not just for patients with ulcerative colitis (UC), but also patients with Crohn disease (CD), particularly those with Crohn colitis. While our understanding of the clinical and molecular basis for this association has improved since the first case descriptions and series were reported nearly a century ago, our means of prevention and treatment, primarily colonoscopic surveillance and prophylactic surgery, remain modest, though circumstantial evidence supports their use. CRC still accounts for a large proportion of the premature mortality in both UC and CD. This chapter will review the pathogenesis and clinical epidemiology of CRC in IBD, as well as the theoretical and literature-based strategies for CRC prevention. Additionally, the available evidence on the association between Crohn ileitis and small intestinal cancer will be presented.