Aspirin use for prevention of cancer

The anti-cancer benefits of daily aspirin were first reported in preventing recurrent colorectal adenomas1,2 and subsequently in the primary prevention of colorectal cancer.3,4 Aspirin is currently recommended to prevent recurrent adenoma but no guidance is provided as to the optimal dose.5

Large randomised trials of alternate-day aspirin found no associated reduction in risk of colorectal cancer or overall cancer incidence or mortality.6,7 

Recent meta-analyses suggest daily aspirin reduces incidence and mortality in other common cancers. Doses ranging from 75mg to 500mg were found to reduce cancer mortality by 15–20% with sustained risk reduction up to 20 years.8,9 

Aspirin also reduced the long-term incidence of cancer by 20–26%3,4,8,9 and prevented metastasis, especially in adenocarcinomas.10

The effects are more pronounced with increasing duration of