Will a 5-ASA a day keep the cancer (and dysplasia) away?

Prevention strategies for colorectal cancer in chronic ulcerative colitis (UC) are currently based on the identification of neoplasia by surveillance colonoscopy, but there is a great interest in the possibility of primary chemoprevention. 5-aminosalicylic acid (5-ASA) therapy is an attractive option for chemoprevention in UC due to the fact that it is a derivative of aspirin and has been shown to have a variety of other molecular and genetic targets of cancer prevention, but human studies in UC have been limited by observational design and limited data collection or follow-up. The recently performed metaanalysis of 5-ASA chemoprevention trials shows a favorable role of 5-ASA in the prevention of cancer and dysplasia in patients with UC, and adds to the available evidence favoring its use. This editorial discusses the substantial logistical and ethical challenges in designing a randomized double-blind trial to measure the effect of 5-ASA on cancer risk in UC. The authors conclude that the safety and current maintenance use of 5-ASA warrant its acceptance as a probable chemopreventive agent at this time.