Both aspirin and omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA), reduced the number of precancerous colon polyps in patients found to be at high risk of developing bowel cancer, according to new research published in the journal Lancet. This study, called the seAFOod Trial, is the result of a multidisciplinary collaboration between the Universities of Leeds, Nottingham, Bradford and Newcastle, as well as others.
The trial was launched to determine whether aspirin or EPA could reduce the number of people who had any polyps at their one year follow up test.
Individuals aged 55–73 years, who were identified as high risk at a complete National Health Service (NHS) Bowel Cancer Screening Programme (BCSP) in England, with three or more colorectal adenomas, at least one ≥10 mm in diameter, or five or more colorectal adenomas that were <10 mm in diameter) were screened for trial eligibility.
Between Nov 11, 2011, and June 10, 2016, 709 participants were randomly assigned to four treatment groups (176 to placebo, 179 to EPA, 177 to aspirin, and 177 to EPA plus aspirin. They took either a 300 milligram aspirin tablet; 2 grams EPA in four capsules; a combination of both aspirin and EPA; or placebos only.
The clinical trial found that both aspirin and EPA reduced the number of bowel polyps in patients one year on from a screening colonoscopy, although they did not reduce the chances of an individual having any polyps present in the bowel. Other findings include:
- Patients taking aspirin had 22% fewer polyps at the end of the one year study compared to those who took the placebo.
- Among the patients who took aspirin, and developed fewer polyps overall, there were fewer polyps on the right side of the large bowel, which is most difficult to monitor by colonoscopy being furthest from the back-passage.
- Those on EPA had 9% fewer polyps at the end of the study compared to those who took the placebo, although this difference was not statistically significant.
- Patients who took EPA had 25% fewer polyps in the left side of the bowel compared to those who took the placebo.
- Although aspirin and EPA had beneficial effects on polyp number on their own, the combination of aspirin and EPA together appeared to have an even greater effect. However, the trial was not designed to provide a definitive answer about combination treatment and further research is needed to test aspirin and EPA treatment together for polyp prevention.
- Treatment with aspirin and EPA was safe with no increased bleeding risk seen. Individuals who took EPA on its own had a slight increase in stomach-upset symptoms.
The seAFOod Trial demonstrates that both aspirin and EPA have preventative effects, which is particularly exciting given that they are both relatively cheap and safe compounds to give to patients. Given this new evidence, clinicians need to consider these agents for patients at elevated risk of bowel cancer, alongside regular colonoscopy surveillance.” ~ Mark Hull, PhD FRCP, Professor of Molecular Gastroenterology at the University of Leeds
Colon and rectal cancer are within the top three types of cancer deaths in the U.K and U.S, with an estimated 50,000 deaths in the United States and 16,000 deaths in England and Wales. While screening is an effective measure, prevention is as important.
“Prevention is key in this common disease and it’s fascinating that the combination of widely available and relatively cheap drugs seemed to have such an impact,” said Professor David Crossman, Interim Director of the NIHR’s Efficacy and Mechanism Evaluation (EME) Programme,
The study suggests that a ‘precision medicine’ approach may be the most appropriate way to use aspirin and omega-3 to prevent bowel polyps, in which patients at risk of particular types of polyps are given treatment specific to that risk.
Conclusion / “The seAFOod Polyp Prevention trial showed that the omega-3 PUFA EPA (2 g FFA per day) and aspirin (300 mg per day) did not reduce colorectal adenoma risk (as measured by the proportion of participants with at least one adenoma) at 1 year surveillance colonoscopy in individuals at high risk with colorectal neoplasia in the English BCSP,” according to the Lancet study.
“However, both agents had some chemopreventive efficacy on colorectal adenoma burden, as measured by a reduction in the mean number of adenomas per participant. The colorectal adenoma subtype-dependent and location-dependent specificity of EPA and aspirin are consistent with previous observations. Existing data on colorectal cancer risk reduction by aspirin suggest that the decrease in colorectal adenoma recurrence reported for both agents is likely to translate into a clinically meaningful decrease in long-term colorectal cancer risk,” said the study.