A daily dose of aspirin halves the risk of bowel cancer in people with Lynch syndrome – one of several genetic conditions that carry a very high risk of bowel cancer.
The study, involving Australian researchers and published in the prestigious international journal The Lancet, is the first intervention study to show that aspirin has a protective effect against cancer.
It supports evidence from previous observational studies that aspirin is more than just a pain reliever and anti-inflammatory drug.
The new study involving almost 900 people with Lynch syndrome, also known as hereditary nonpolyposis colorectal cancer (HNPCC), found two aspirin a day for two years reduced the risk of bowel cancer by about 60 per cent.
The aspirin also halved the risk of other cancers such as ovarian cancer which are associated with Lynch syndrome but had no impact on cancers such as lung cancer which are not associated with Lynch syndrome.
About 1 in 1,000 people carry Lynch syndrome genes which results in a high risk of developing bowel and other cancers, and at an earlier age than with non-genetic cases.
The genetic mutation affects the body’s ability to repair damaged DNA – particularly important in places such as the bowel where the lining is renewed constantly.
The authors said there were several plausible mechanisms by which aspirin could reduce bowel cancer but more research was needed.
- Aspirin is already known to block key enzymes involved in the process of inflammation which may also influence the development of bowel cancers.
- Aspirin may also block the development of new blood vessels required for bowel polyps to progress to cancer.
- Aspirin enhances the body’s ability to destroy abnormal cells.
The study group, who were typically aged in their 40s and did not include anyone with a known sensitivity to aspirin, experienced few side effects from the aspirin. However the researchers said side effects such as gastric ulcers were possible with high dose aspirin.
A subsequent study aims to determine the optimal dose for protection against bowel cancer with minimal side effects.
Regular low does aspirin is already recommended by cardiologists to help reduce the risk of cardiovascular disease such as heart attacks and thrombotic stokes through its ‘blood thinning’ properties.
Click here for further details on bowel cancer and family history, including genetic inheritance.