Aspirin can reduce the risk of some cancers, and scientists are starting to understand why, according to a growing body of research.
The drug, whose origins can be traced back thousands of years to remedies made from willow bark, is most commonly used to relieve pain, but it also appears to prevent certain tumours from forming and spreading.
Studies over several decades have suggested that people taking aspirin regularly may have a lower risk of developing some forms of cancer, particularly those affecting the digestive system.
Researchers believe part of the explanation may lie in how aspirin affects inflammation and blood platelets, which cancer cells can exploit as they spread through the body.
“An ancient, inexpensive drug may still have important lessons to teach us about how cancer spreads.”
“We have known for some time that aspirin seems to have a protective effect, and now we are beginning to see the biology behind it,” said one cancer researcher.
Scientists hope a clearer understanding of the mechanism could help identify which patients are most likely to benefit, and lead to more targeted treatments.
However, doctors stress that aspirin is not suitable for everyone, as regular use can increase the risk of internal bleeding and other side effects.
Health experts advise people not to start taking aspirin daily to prevent cancer without first discussing the risks and benefits with their doctor.
Interest in the drug's anti-cancer potential has grown alongside wider efforts to find low-cost ways of preventing disease, as researchers look for treatments that could be used widely without placing heavy financial strain on health systems.
Further clinical trials are under way to determine the right doses and the groups of patients for whom the potential benefits clearly outweigh the risks.
