Aspirin and the prevention of colorectal cancer

A substantial body of evidence from observational studies and randomized trials indicates that regular aspirin use reduces the risk of incident and fatal colorectal cancer. Despite what many would consider compelling support for aspirin’s efficacy as a chemopreventive agent, concerns regarding toxicity have thus far limited its widespread adoption for the primary prevention of colorectal cancer in average-risk individuals. Uncertainties remain regarding the optimal dose and duration of therapy. The molecular mechanisms that underlie the antineoplastic effects of aspirin are also incompletely understood. Importantly, it is unclear whether there are net benefits associated with aspirin use for all subgroups of the population. Nonetheless, we are likely to experience an increasing trend toward recommending aspirin for a broader range of indications, including cancer prevention. The identification of biomarkers of aspirin benefits and harms, which would facilitate precision chemoprevention strategies, constitutes a key research priority.