Asprin does not reduce breast cancer risk
Taking low-dose aspirin does not reduce a woman's risk of breast cancer, suggests a new study contradicting previous findings.
Aspirin is a known inhibitor of the enzymes cyclooxygenase 1 and 2 and COX-2 overexpression stimulates prostaglandin E2 production, which in turn stimulates aromatase transcription, resulting in increased concentrations of oestradiol.
It has been suggested that regular aspirin use could reduce future risk of cancer by decreasing endogenous oestrogen production.
But US researchers reviewed data from 39,876 women with no history of breast cancer randomised to receive 100mg aspirin a day or placebo for 10 years.
They found 762 women taking aspirin developed breast cancer compared with 779 women taking placebo – a non significant difference.
British Journal of Cancer 2008 20 February early online publication