Can we select patients for colorectal cancer prevention with aspirin?

Aspirin has been extensively investigated in the context of the prevention of cardiovascular disease. It has one of the strongest cumulative evidence supporting its use in colorectal cancer (CRC) chemoprevention. Epidemiological, clinical, and observational studies have demonstrated that aspirin and non-steroidal antiinflammatory drugs (NSAIDs), including COX-2 inhibitors, can protect against CRC and significantly reduce its incidence. Moreover, prospective randomized controlled trials of colorectal polyp recurrence and in patients with hereditary CRC syndromes have shown that aspirin can produce regression of existing colorectal adenomas and prevent the formation of new polyps. However, the lowest effective doses, treatment duration, target populations, and the effects on survival are not entirely clear. Although not common serious side effects and in particular gastrointestinal and intracerebral hemorrhage do occur, better selection of individuals who might benefit the most from aspirin use must be carefully performed in order to maximize their risk/benefit ratio. In the era of precision medicine, genetic information, blood and/or urinary biomarkers, could potentially help in tailoring chemopreventive therapeutic strategies, based on aspirin use, while limiting adverse toxic effects. The current review will cover the use of aspirin for the prevention of colorectal adenomas and CRC, potential markers for chemoprevention, and patient stratification.