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
Millions through license revenues
27.04.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn
New High-Performance Center Translational Medical Engineering
26.04.2017 | Fraunhofer ITEM
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
28.04.2017 | Event News
20.04.2017 | Event News
18.04.2017 | Event News
28.04.2017 | Medical Engineering
28.04.2017 | Earth Sciences
28.04.2017 | Life Sciences