Daily aspirin reduced deaths from prostate cancer (PCa) and some other common cancers during and after eight randomized trials comparing the regimen with placebo.
Data from 25,570 study subjects participating in trials of at least four years’ duration demonstrated that aspirin use decreased cancer mortality by 21%. After five years’ follow-up, mortality rates fell by 54% for gastrointestinal cancers and 34% for all cancers.
The overall effect on 20-year risk of cancer death was greatest for adenocarcinomas: Aspirin users experienced a 20% lower risk of death than placebo recipients, with a 10% reduced risk observed for prostate cancer. The latent period before an effect on deaths was about five years for esophageal, pancreatic, brain, and lung cancers, but about 15 years for PCa. Peter M. Rothwell, of John Radcliffe Hospital, Oxford, and the University of Oxford, U.K., and fellow investigators noted in online report in The Lancet that the benefit of daily aspirin on cancer increased with duration of treatment and with patient age, was unrelated to aspirin dose (75 mg and up), gender, and smoking status. The effect was consistent across all study populations.