Low-dose aspirin seems to increase survival and reduce metastatic spread in people being treated for some cancers, according to a new metaanalysis published in PLoS ONE.
Based on 29 studies, taking aspirin after the diagnosis of colorectal cancer reduces mortality from the malignancy by 28 per cent. Based on 14 and 16 studies, taking aspirin reduces mortality from breast and prostate cancer by 31 and 13 per cent respectively.
Ten studies assessed aspirin’s effect on metastatic spread. Depending on the statistical analysis, aspirin reduced the risk of metastatic spread by 21 or 69 per cent, based on five and four studies respectively. The researchers identified 15 studies assessing aspirin in other malignancies. Ten suggested aspirin might be beneficial, with the differences reaching statistical significance in six trials.
“There is much favourable evidence on the three main cancers, but very little on the less common cancers, although what is available is ... encouraging,” the authors comment. The studies also offer some reassurance about the risk of haemorrhage with little evidence of an increase in serious bleeds, they say.
Further research needs to determine the optimal dose of aspirin and risk of serious and fatal bleeding. The authors say their findings merit discussion regarding whether the evidence is adequate to justify the recommendation of low-dose aspirin, and if it is, for which cancers.