Aspirin may block the growth of colorectal tumours with a specific genetic mutation
Researchers affiliated with the Harvard Medical School reported that aspirin was associated with a prolonged life of patients with tumours that carried the mutated PIK3CA gene – 97% of these people who commenced regular aspirin after diagnosis were alive after five years, compared to 74% who did not take aspirin.
Professor Finlay Macrae, Head of Colorectal Medicine and Genetics at The Royal Melbourne Hospital, said one of the most interesting aspects of this study was that it looked at the effects of aspirin in a chemotherapy setting.
“The pathways and targets in established cancer are being better defined,” said Prof Macrae, who works on the cancer component of the largest primary prevention aspirin study in older adults, ASPREE (ASPirin in Reducing Events in the Elderly).
“As we discover more genetic markers such as the PIK3CA mutation, doctors will be able to target therapies specific to the type of tumour,” said Prof Macrae.
He cautioned that this colorectal cancer study provided preliminary data only – there were only 66 people with the genetic mutation in the study, the dose of aspirin was not clearly defined and any potential benefit of aspirin must be weighed against risks, such as bleeding.
“This research demonstrates an additional link between aspirin and bowel cancer, which supports the inclusion of colorectal cancer survivors into large randomised studies such as ASPREE,” said Prof Macrae.
“ASPREE will have the critical mass to establish the association between colorectal cancer and aspirin but most importantly, it will weigh the benefits versus the risks.”
Colorectal cancer is the second most common newly diagnosed cancer in Australia. According to Bowel Cancer Australia, if bowel cancer is detected early, the chance of survival beyond five years was around 90%.
Researchers found that aspirin taken after diagnosis was not shown to reduce tumour growth in other types of colorectal cancer without the PIK3CA mutation.
Approximately 15-20% of people diagnosed with colorectal cancer are estimated to have mutated PIK3CA colorectal tumours.
The research was published in the New England Journal of Medicine.