But the authors of the study and an accompanying comment stress that the potential risks of long term aspirin use at this dose and the availability of alternative prevention strategies mean that widespread use of aspirin for cancer prevention cannot be recommended in the general population.
However, the benefits are likely to outweigh the risks in individuals at increased risk of colon cancer. The findings are also likely to influence the choice of antiplatelet drug in patients who require long-term treatment because of vascular disease.
The study was conducted by Professor Peter Rothwell, University Department of Clinical Neurology, Radcliffe Infirmary, Oxford, UK and colleagues. In collaboration with the original investigators (Sir Richard Doll, Sir Richard Peto and Charles Warlow), they determined the delayed effect of aspirin by following-up patients from two large randomised trials of aspirin performed in the late 1970s and early 80s - the British Doctors’ Aspirin Trial and the UK-TIA Aspirin Trial.
The researchers were particularly interested in long term follow-up due to the likely time delay in any effect of aspirin on colorectal cancer. Adenomas (the pre-cancerous growths that aspirin is thought to reduce) take at least 10 years to develop into cancers. The study showed that use of Aspirin for five years reduced the subsequent incidence of colorectal cancer by 37% overall, and by 74% during the period 10-15 years after treatment was started.
In an accompanying analysis of observational studies, the risk of colorectal cancer also appeared to be reduced by between 50-70% in patients taking medium-high doses of aspirin for 10 years or more. This analysis also showed that the effects of aspirin were consistent regardless of age, sex, race or country of origin of patients studied (all of which affect the general rate of colorectal cancer) and that the effect was also seen in individuals with a family history of colorectal cancer in a first degree family relative (which increases lifetime risk of an individual acquiring the disease by two to four times).
The authors conclude: “Use of 300mg or more of aspirin a day for about five years is effective in primary prevention of colorectal cancer, with a latency of about 10 years, which is consistent with findings from observational studies.
“Long-term follow up is required from other randomised trials to establish the effects of lower or less frequent doses of aspirin.”
In an accompanying comment, Dr Andrew Chan, Gastrointestinal Unit, Massachusetts General Hospital, Boston, USA, says: “Rothwell and colleagues’ results, when viewed in the context of the preponderance of laboratory studies, epidemiological data, and adenoma recurrence trials, do provide convincing evidence that aspirin, at biologically relevant doses, can reduce the incidence of colorectal cancer.
“However, with the concerns about the potential risks of long-term aspirin use and the availability of alternative prevention strategies (e.g. screening), these findings are not sufficient to warrant a recommendation for the general population to use aspirin for cancer prevention.”
Tony Kirby | alfa
New antibody analysis accelerates rational vaccine design
09.08.2018 | Scripps Research Institute
Distrust of power influences choice of medical procedures
01.08.2018 | Johannes Gutenberg-Universität Mainz
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur
What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...
The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.
Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends...
If certain signaling cascades are misregulated, diseases like cancer, obesity and diabetes may occur. A mechanism recently discovered by scientists at the Leibniz- Forschungsinstitut für Molekulare Pharmakologie (FMP) in Berlin and at the University of Geneva has a crucial influence on such signaling cascades and may be an important key for the future development of therapies against these diseases. The results of the study have just been published in the prestigious scientific journal 'Molecular Cell'.
Cell growth and cell differentiation as well as the release and efficacy of hormones such as insulin depend on the presence of lipids. Lipids are small...
08.08.2018 | Event News
27.07.2018 | Event News
25.07.2018 | Event News
14.08.2018 | Medical Engineering
14.08.2018 | Life Sciences
14.08.2018 | Life Sciences