Safety and efficacy of aspirin for primary prevention of cancer: a meta-analysis of randomized controlled trials.

Our study did not find any significant reductions in cancer-related mortality or cancer incidence when compared aspirin use with placebo or no aspirin. Our study also highlights that the use of aspirin for primary prevention of cancer was found to cause higher rates of bleeding (any bleeding, major bleeding, and GI bleeding) compared to placebo or no aspirin at the longest follow-up period with no significant benefit in cancer primary prevention.