[Chemoprevention of colorectal cancer]

Although colorectal cancer is one of the most preventable forms of cancer, it remains the second leading cause of cancer death worldwide. Primary prevention involves the identification and elimination of factors, which cause or promote colorectal cancer. The goal of screening is to prevent colorectal cancer mortality through the detection and treatment of premalignant adenomas and curable-stage cancer. Most colorectal cancers are believed to arise from adenomatous polyps. Early identification and removal of adenomas can prevent the development of colorectal cancer. Chemoprevention is the use of specific chemical compounds to prevent, inhibit, or reverse carcinogenesis. Several chemoprevention options have been investigated and confirmed as effective. Aspirin and other nonsteroidal anti-inflammatory drugs are the most widely studied agents, their use has been consistently associated with reduction in the risk of mortality and the incidence of colorectal adenomas and cancers. The selective cyclooxygenase-2 (COX-2) inhibitors (coxibs) have been demonstrated to decrease the number and the size of polyps in patients with familial adenomatous polyposis syndrome. Because the gastrointestinal toxicity of coxibs is lower, it might be safer than aspirin or other non-selective nonsteroidal anti-inflammatory drugs for long-term use. This review aims to summarize the recent theoretical and practical advances in the chemoprevention of colorectal cancer.