Daily aspirin said to cut cancers by a quarter

THE century-old painkiller aspirin seems set for a fresh surge in popularity after researchers found it dramatically cuts the risk of developing cancer, as well as halving the chance of existing tumors seeding themselves to spread throughout the body.

Three linked papers published yesterday in one of the world's top medical journals found a daily aspirin cut the number of cancers diagnosed by 23 per cent in men and 25 per cent in women, while the risk of dying from cancer was cut by 15 per cent -- rising to 37 per cent among those who kept taking the aspirin for five years or more.

The results, based on a re-analysis of more than 50 previous studies, also found that cancers were nearly half as likely to spread elsewhere in the body if patients were taking aspirin for six years -- a finding the authors from the University of Oxford said provided the "first proof in humans" that aspirin prevents the spread of cancers.

Previous studies have linked aspirin to reduced rates of colon and some other cancers, but the new findings, published online in The Lancet and The Lancet Oncology, suggest the protective effect is far more significant.

Australian experts hailed the results. Cancer Council Australia chief executive Ian Olver described the findings as "dramatic". "If you had a cancer treatment that did that, it would be front-page news," he said.

"But I don't think we know the best dose to take . . . we should get the dose and scheduling right before we tell everyone to take daily aspirin.

"At the moment, we don't know if we need to take low-dose, high dose, or if you can take it intermittently or if you need to take it every day."

The findings suggest aspirin may have benefits beyond preventing heart attacks, an effect discovered in the 1980s and linked to the fact that the drug thins blood and helps prevent clotting.

Millions of people take low-dose aspirin for this reason, but in recent years there has been a push to recommend this only for patients who have already had a heart attack because the drug also increases the risk of gastro-intestinal bleeding.

Professor Olver said the studies were reassuring on this point, showing that the negative effect of bleeding diminished over time, and was outweighed by the reduction in cancer risk after three years.

A linked editorial published in The Lancet said that the studies had some weaknesses -- including the fact that they did not include the two biggest trials of aspirin prevention, neither of which had shown any reduction in cancer cases or deaths after 12 years of follow-up.  (theaustralian.com.au)