7 Dec 2010

Aspirin: the new anti-cancer ‘miracle drug’

New scientific research suggests that daily low doses of aspirin could help middle-aged people reduce the risk of dying of a range of cancers.

The drug is already recommended as a way of warding off heart attacks and strokes for those at risk, but the new research – published today by The Lancet – has moved aspirin to the level of a “miracle drug”.

The study leader – Professor Peter Rothwell, of Oxford University – said the results did not mean that all adults should immediately start taking aspirin, but did change the balance of risk against the possible side-effects of causing stomach bleeding.

“Previous guidelines have rightly cautioned that in healthy middle-aged people the small risk of bleeding on aspirin partly offsets the benefit from prevention of strokes and heart attacks, but the reductions in deaths due to several common cancers will now alter this balance for many people,” he said.

The research brought together eight different studies involving more than 25,000 patients over a number of years. Much of this had previously been “lost”, as the studies were centred on other aspects of the treatment.

Significant benefits

But the Rothwell team said that the patients – taking at least 75mg of aspirin every day (about a quarter of a regular aspirin tablet) for between four and eight years – showed significant benefits after five years of follow-up, with death rates for all cancers falling by 34 per cent and for stomach and bowel cancers by 54 per cent.

After 20 years, the risk of death among those who had taken regular doses of aspirin remained 20 per cent lower for all solid cancers and 35 per cent lower for stomach and bowel cancer.

The demon disease is preventable
These results mark a sea change in the way we think about cancer, writes Science Correspondent Julian Rush. The demon disease is preventable. And it can be tamed by a drug as simple and as humble as aspirin.

Just as aspirin changed the way we approached the risks of heart disease and stroke, the research by the Oxford team caps what has been a growing body of research that some cancers, at least, can be prevented.

It will surely act a spur to scientists, for more evidence is needed to properly quantify the benefits: double blind, placebo-controlled clinical trials to prove, once and for all, that the benefits outweigh the risks - of stomach bleeding, for example.

Such trials take time, but Professor Peter Sasieni, the Director of the Cancer Prevention Trials Unit at the Wolfson Institute of Preventative Medicine at Queen Mary, University of London, is optimistic.

"Already they're saying that people at high risk of bowel cancer should just be given aspirin. We just can't do the trials any more because I don't think anyone could honestly 'it's not a good idea for you to take aspirin'".

Adding in previous research, the drug appears to have an effect in combatting cancers affecting the stomach and bowel, the oesophagus, the pancreas, the lungs, the prostate, the bladder and the kidneys. Two recent studies had suggested that regular doses of aspirin reduced the risk of death from bowel cancer by a third and – for men – of developing prostate cancer by up to 30 per cent.

The researchers suggest that the peak age at which most benefit could be gained from taking aspirin is between 45 and 50, which is when most cancers start to develop.

Millions of Britons at risk of heart disease or strokes already take low doses of the drug on a regular basis.

Professor Peter Elwood – an epidemiologist from the University of Cardiff who has carried out his own research on aspirin – said that taking the drug at night and with calcium – such as with milk – seemed to enhance the effects.

It is so far unclear how the drug works against cancer, but it is believed to boost mechanisms that either repair damaged DNA or cause potentially dangerous cells to commit suicide.

“These promising results build on a large body of evidence suggesting that aspirin could reduce the risk of developing or dying from many different types of cancer.” Ed Yong, Cancer Research UK

The risk of gastro-intestinal bleeding – just one in 2,000-3,000 for the general population – was doubled by taking aspirin on a regular basis, but there was no evidence of any increased risk of death from this, he added.

Both Prof Rothwell and Prof Elwood said that they themselves took a low dose of aspirin every day.

Ed Yong, from the charity Cancer Research UK, said that anyone interested in taking aspirin on a regular basis should first consult their GP. But he added: “These promising results build on a large body of evidence suggesting that aspirin could reduce the risk of developing or dying from many different types of cancer.

“While earlier studies suggested that you only get benefits from taking high doses of aspirin, this new study tells us that even small doses reduce the risk of dying from cancer provided it is taken for at least five years.”