A junior aspirin (75 mg) a day might keep cancer at bay was the headline-grabbing cancer story this month. In a report published in The Lancet, Peter Rothwell and colleagues from the University of Oxford, UK, found that patients who regularly take the humble aspirin for other ailments for 5 years or more have a reduced incidence of prostate, stomach, colorectal, oesophageal and lung cancer.

Rothwell and colleagues carried out a meta-analysis of eight randomized trials involving 25,570 patients and found that those who had taken aspirin and not the placebo in these trials had a 20% reduced incidence of death from solid tumours over a 20-year period. Given that this effect seems to be more substantial than that of aspirin on preventing heart attacks or stroke, Rothwell stated that “...I think in the fullness of time, preventing cancer will be seen to be the main reason for taking aspirin in healthy individuals.” ( Time Healthland , 7 Dec 2010).

However, despite its well-characterized anti-inflammatory properties that probably explain this effect, both Rothwell and other doctors have stopped short of urging everyone to take aspirin because of its risk of inducing haemorrhage. Dominique Thompson, of the University of Bristol's health service, UK, said “It would seem that GPs will have a real opportunity to improve certain people's life quality and expectancy in the future but only if we have a clearer idea of who might benefit from long-term use of low-dose aspirin.” ( Bristol Evening Post , 8 Dec 2010).

Professor Allan Spigelman, Director of St Vincent's Clinical School, University of New South Wales, Australia, stated that the effect of aspirin needs to be kept in perspective “if say 100,000 people [took] low dose aspirin for five years, it would prevent 56 cancer deaths”. ( The Sydney Morning Herald , 7 Dec 2010).