Gastrointestinal malignancy in Crohn's disease

Crohn's disease may be associated with carcinoma affecting the anorectum, colon, small intestine or upper gastrointestinal tract. The extent to which this risk applies and how it should be managed remain controversial. Epidemiological and clinicopathological studies indicate patients with chronic complicated anorectal or intestinal disease and individuals with extensive Crohn's colitis are at most risk of cancer. Such patients require regular clinical supervision, and a low threshold for surgery is applicable for those with chronic disabling symptoms, or if a precancerous or cancerous lesion is suspected. At present, there are no data supporting the efficacy of surveillance in preventing cancer-related mortality, though its role in extensive Crohn's colitis deserves specific evaluation.