Colorectal cancer ranks among the most common malignancies in the United States and other economically developed countries. At current rates, approximately 6 percent of individuals will develop this malignancy in their lifetime. Approximately one-half of individuals diagnosed with colorectal cancer will die from it. (See "Colorectal cancer: Epidemiology, risk factors, and protective factors".)
The risk of colorectal cancer can be reduced by screening, recommendations for which have been issued by several major medical organizations. (See "Screening for colorectal cancer: Strategies in patients at average risk".)
In addition, several protective factors have been identified, stimulating interest in primary prevention. (See "Colorectal cancer: Epidemiology, risk factors, and protective factors".)
Among the protective agents are aspirin and other nonsteroidal antiinflammatory drugs (NSAIDs). A large and compelling body of research has shown that NSAIDs inhibit colorectal carcinogenesis. The evidence is diverse and is based upon animal models, epidemiologic data, intervention trials of NSAIDs in patients with familial polyposis, and, more recently, randomized controlled trials of aspirin and selective COX-2 inhibitors in humans.
This topic review will summarize the data supporting the potentially beneficial role of aspirin and other NSAIDs for colorectal cancer, and discuss the potential clinical implications. The potential benefits of aspirin for the incidence and mortality of other cancers is discussed separately. (See "Aspirin in the primary prevention of cardiovascular disease and cancer".)