Prevention of colorectal cancer in inflammatory bowel disease

Colorectal cancer is a serious complication of inflammatory bowel disease. The persistent inflammatory triggers are thought to lead to genetic alterations and malignant degeneration, but the precise pathogenesis of the problem – which appears to be different from the “classic” adenoma-carcinoma sequence – has not yet been unravelled. Nevertheless, both extent and severity of the inflammation are thought to contribute to triggering malignant degeneration.

Given this fact, it is necessary to examine the opportunities for current and future approaches to colorectal cancer prevention. The authors evaluated the value of surveillance colonoscopy and chemoprevention of colorectal cancer with 5'-aminosalicylic acid, and review the current state of knowledge in the epidemiology of and new approaches to the prevention of cancer and dysplasia in inflammatory bowel disease.

The authors conclude that there is significant preclinical and clinical evidence to suggest that 5-aminosalicylate drugs reduce the risk of colorectal neoplasia. However, the minimal dosage to achieve this chemopreventive effect remains unclear. There is also indirect evidence to suggest that surveillance colonoscopy is beneficial for patients with inflammatory bowel disease, particularly in those with long-standing pancolitis or primary sclerosing cholangitis-associated inflammatory bowel disease. However, definitive proof from prospective clinical trials is not yet available, and more research needs to be performed.