Three new studies published in the March 21, 2012 online edition of the medical journal The Lancet suggest common aspirin may significantly reduce the risk of many cancer types and prevent tumors from spreading.
The studies, co-authored by Peter M. Rothwell, a researcher and professor of clinical neurology at the University of Oxford in England, add to a growing body of evidence that aspirin could be an inexpensive and widely available tool to fight cancer.
But you might want to consider some facts before running to your medicine chest.
Past studies have suggested daily aspirin use can have its drawbacks too, particularly in health people, such as gastrointestinal bleeding, hampering your ability to form blood platelets, which causes blood to clot and stops bleeding at the site of a wound.
Other side effects of taking too much aspirin can be tinnitus — known as ‘ringing in the ears’ — which can cause eventual hearing loss in some people or sometimes-serious allergic reactions.
A daily aspirin regimen is already used for some people at higher-than-normal risk of colorectal cancer because it can lower inflammation in the colon. However, for people at normal risk of colon cancer, the recommendation as viewed by health professionals, is controversial.
For one of the studies, researchers at University of Oxford found after three years of daily aspirin use , the risk of developing cancer was lowered nearly 25 percent when compared to a control group not taking aspirin. After five years, the risk of dying in the aspirin group was reduced 37 percent.
To determine these results, the researchers use patient data from many large, long-term randomized control trials involving tens of thousands of men and women.
A second paper analyzed five large randomized controlled studies in Britain found patients using daily aspirin for an average of six and a half years reduced their risk of metastic cancer by 36 percent. The news was even better for adenocarcinomas — common solid cancers, including colon, lung and prostate cancer — which saw a 46 percent reduction.
Daily aspirin lowered the risk of progressing to metastatic disease, particularly in patients with colorectal cancer, the studies reported. A third study compared the findings of observational studies and randomized trials of aspirin.
There is an urgent need for clinical trials of treatment regimens incorporating aspirin, Dr. Rothwell said.
“What really jumps out at you in terms of prevention is the striking 75 percent reduction in esophageal cancer and a 40 to 50 percent reduction in colorectal cancer, which is the most common cancer right now,” Dr. Rothwell told the New York Times. “In terms of prevention, anyone with a family history would be sensible to take aspirin.”
Eric J. Jacobs, Ph.D., a senior epidemiologist with the American Cancer Society's Department of Epidemiology and Surveillance Research says the studies provide “important new evidence that taking aspirin long-term could lower the risk of developing cancer, but taking aspirin won’t be right for everyone.”
“Because these results are new, it will take time for the broader scientific community to evaluate the data in the context of existing knowledge and to consider whether the clinical guidelines should be changed,” he said.
Jacobs says clinical guidelines require a systematic analysis so researchers can better understand for whom the benefits of aspirin use will likely outweigh the risks, and when it might pose serious health consequences.
“For now, any decision about [taking aspirin for cancer prevention or] treatment should be made on an individual basis in consultation with your health care professional,” Jacobs said.
Lynette Summerill is an award-winning writer and Scuba enthusiast living in San Diego, CA with her husband and two beach loving dogs. In addition to writing about cancer-related issues for EmpowHER, her work has been seen in newspapers and magazines around the world.
Sources and patient information:
Short-term effects of daily aspirin on cancer incidence, mortality and non-vascular death: analysis of the time course of risks and benefits in 51 randomised controlled trials. Rothwell, Peter M., et al. The Lancet, Early Online Publication, 21 March 2012.doi:10.1016/S0140-6736(11)61720-0
http://www.thelancet.com/journals/lancet/article/PIIS0140-6736%2811%2961720-0/fulltext
Effect of daily aspirin on risk of cancer metastasis: a study of incident cancers during randomized controlled trials. Rothwell, Peter M., et al. The Lancet, Early online Publication, 21 March 2012. doi:10.1016/S0140-6736(12)60209-8 Access online at:
http://www.thelancet.com/journals/lancet/article/PIIS0140-6736%2812%2960209-8/fulltext
Effects of regular aspirin on long-term cancer incidence and metastasis: a systematic comparison of evidence from observational studies verses randomized trials. Algra, A.M. and Rothwell, P.M., The Lancet Oncology, Early Online Publication, 21 March 2012. doi:10.1016/S1470-2045(12)70112-2. Access online at:
http://www.thelancet.com/journals/lanonc/article/PIIS1470-2045%2812%2970112-2/fulltext#
Daily Aspirin Therapy: Understanding benefits and risks. Mayo Clinic. Access online at:
http://www.mayoclinic.com/health/daily-aspirin-therapy/HB00073
American Cancer Society. Eric Jacobs, Ph.D. 16 March 2012.
Studies Link Daily Doses of Aspirin to Reduced Risk of Cancer. New York Times. Roni Caryn Rabin 20 March 2012. Access online at
http://www.nytimes.com/2012/03/21/health/research/studies-link-aspirin-daily-use-to-reduced-cancer-risk.html
Reviewed March 29, 2012
by Michele Blacksberg RN
Edited by Jody Smith