Risk of bowel cancer reduced by taking aspirin for Lynch syndrome patients

An international study led by The University of Melbourne has confirmed that long-term regular taking of aspirin or ibuprofen reduces the risk of bowel cancer by more than half for people with the genetic mutation causing Lynch syndrome.

At least 1 in 1000 people in the population have the genetic mutation that causes Lynch syndrome. These people have a much higher rate of bowel cancer than the general population and about half would develop the disease without regular screening.

In a paper published in the Journal of the National Cancer Institute, University of Melbourne researchers and international collaborators, led by Dr Driss Ait Ouakrim and Dr Aung Ko Win from the School of Population and Global Health confirmed that those with Lynch syndrome who took aspirin regularly were less likely to develop bowel cancer than Lynch syndrome patients who did not take aspirin.

The research team also uncovered a new finding that Lynch syndrome patients who took ibuprofen regularly, another nonsteroidal anti-inflammatory drug, were about 60% less likely to develop bowel cancer compared with those who did not take ibuprofen. This protection was seen in both men and women.

"The main risk reduction method for these people is to have regular colonoscopy screening. Almost nothing is known about if and how lifestyle factors and medications can modify their risk of bowel cancer," Dr Win said.

"Our data is the first to confirm the finding of a previous international randomised clinical trial that found a protective effect of aspirin on bowel cancer for these high-risk people. Also, we were able to show the similar protective effect of ibuprofen such as Nurofen on bowel cancer for people with Lynch syndrome," Dr Win said.

These findings are the result of a 15 year study of 1,858 people with Lynch syndrome recruited from Australia, New Zealand, Canada and the USA. This is the largest study to date investigating the associations between aspirin, ibuprofen and bowel cancer risk for people with Lynch syndrome.

Further studies are being conducted to help determine the optimal dose, duration and timing of treatment.