Taking aspirin can boost the survival of cancer patients and reduce the risk of the disease to others parts of the body, say scientists.
Researchers analysed 71 medical studies, which looked at the survival of 120,000 patients with cancer who took aspirin, compared with 400,000 patients who did not.
They showed that at any time following the diagnosis of some cancers the proportion of patients who were still alive was 20-30 per cent greater in those taking the drug.
The spread of cancer to other parts of the body was also substantially reduced in patients using aspirin.
"The use of low-dose Aspirin as a preventive in heart disease, stroke and cancer is well established but evidence is now emerging that the drug may have a valuable role as an additional treatment for cancer too," said Peter Elwood, from Cardiff University in the UK.
One of the colon cancer studies the researchers looked at suggested that a non-diabetic man of about 65 years who takes aspirin would have a prognosis similar to that of a man five years his junior who takes none.
More From This Section
For a woman of similar age with colon cancer the addition of aspirin could lead to a similar prognosis of a woman four years younger.
Almost half the studies included in the review were of patients with bowel cancer, and most of the other studies were of patients with breast or prostate cancer.
There were very few studies of patients with other less common cancers, but on the whole the pooled evidence for all the cancers is suggestive of benefit from aspirin.
The evidence is not entirely consistent and a few of the studies failed to detect benefit attributable to aspirin, researchers said.
More evidence is therefore urgently needed and a number of new randomised trials have been set up, but these are unlikely to report for quite a few years.