THE claims could not be more eye-catching.Speaking at a briefing for medical journalists in London on Tuesday, Professor Jack Cuzick, head of the centre for cancer prevention at the Queen Mary University, said aspirin — the little white painkiller best known for tackling headaches — could in fact be a life-saving weapon in the battle against cancer.
The research, published in the latest edition of peer-review journal the Annals of Oncology, suggests the widely-used drug could potentially prevent tens of thousands of deaths in Ireland over the coming years.
While the findings have serious public health implications, side effects identified in the research need further exploration.
According to an examination of more than 200 clinical trials on aspirin’s anti-cancer effects by Prof Cuzick’s team, when taken every day for a decade or more, the drug can lead to major drops in colorectal (35%), throat (30%), stomach (30%), prostate (10%), lung (5%) and breast (10%) cancer diagnoses among people aged 50 to 64.
In addition, the 75-100 milligram daily dosage can lead to a 40%, 50%, 35%, 15%, 15% and 5% fatality-rate reduction in these cancers over the same period.
Based on these figures, Prof Cuzick has suggested that people aged 50 to 64 should take a daily dose of aspirin for 10 years to significantly reduce the risk of cancer — which could potentially save more than 130,000 lives in Britain alone over the next 20 years.
Prof Cuzick said aspirin “looks like the most important thing we can do to reduce cancer after stopping smoking and reducing obesity, and will probably be much easier to implement.”
He added that while “it has long been known” among cancer experts that aspirin, which he said is “one of the cheapest and most common drugs on the market”, had cancer-fighting effects, “until our study it was unclear whether the pros of taking [it] outweighed the cons.”
However, while the research is groundbreaking, clearly well-founded and supported by other cancer experts, it is not quite as clear-cut as a cursory look suggests.
Although aspirin is showing genuine promise in tackling cancer, an issue which will affect one in three Irish people during their lifetime, its long-term use is also heavily linked to other non-related, yet equally serious illnesses which pose just as much of a risk to someone’s life.
According to the same study, long-term use of the over-the-counter medication increases the risk of stomach bleeds in 60-year-olds from 2.2% to 3.6% — with about 5% of these cases proving fatal.
Despite a 5% drop in stroke cases in people who use aspirin over the same extended period, the number of stroke deaths surges by 21%.
The 130,357 people aged 50 to 64 likely to be alive after 10 years of taking aspirin instead of dying from cancer is added to by what the researchers say would be a further 9,473 also protected from fatal heart attacks, but they admit the widespread daily use of the drug would be likely to cause 18,000 deaths from internal bleeding and strokes.
Although the cancer benefits far outweigh the deaths from other conditions when it comes to counting numbers on a sheet of paper, the Irish Cancer Society’s acting head of research, Dr Sinead Walsh, admits the issue is a medical ‘Sophie’s Choice’ question that poses difficulties the research has yet to fully overcome.
“The use of aspirin to prevent cancer is currently a very hot topic in cancer research,” Dr Walsh confirmed.
“The review by Prof Cuzick this week shows that aspirin has a protective effect against a number of cancers, but aspirin use is also associated with increased risk of lethal strokes, peptic ulcers and gastric bleeds.
“There are still some questions that need to be answered about the age, duration and dose of aspirin that should be taken to prevent cancer, in addition to an individual’s risk of serious side effects,” she said.
Like their colleagues in Britain, the Irish Cancer Society is currently examining the use of aspirin in the fight against various cancers, with researcher Ian Barron being funded by the body to work on the project in Ireland through its collaborative cancer research centre, Breast-Predict.
These studies are also examining how to limit the negative impact of long-term aspirin use on other parts of the body, an issue the Irish Heart Foundation says is needed before the aspirin cancer research can be fully endorsed.
“The results of this study are interesting but, as with many medications, there is a balance between risks and benefits,” IHF cardiologist Dr Jonathan Lyne cautioned.
“Many trials will be undertaken in patients of a particular age and profile, therefore extrapolating these broad conclusions to the general population may not be valid.
“The latest research is not conclusive and requires further investigation and so I would advise all patients to talk to their GP or consultant before deciding to start on a daily course of aspirin as it may not be appropriate for all.”
While welcoming the aspirin research, the Irish College of General Practitioners has issued a similar call for caution.
Its medical director, Dr Margaret O Riordan, said using the drug as a cancer treatment is “still under analysis” and that people should take simpler steps to avoiding cancer such as exercising and improving their diets first.
While the new findings are genuinely impressive and offer a potential breakthrough in the battle against conditions which have cut short countless lives, the responses from independent experts show that legitimate concerns still exist.
At this stage of the aspirin-cancer debate, the question is, does the clear benefit of using the medication on a daily basis for some outweigh the potential risks for others?
Or to put it more bluntly, would you prefer to significantly increase your chances of being cancer free for the rest of your life, on the condition you live with the growing possibility of heart, stroke and potentially fatal stomach ulcers in the years to come?
- While scientists are still examining the exact reason why, they have two workable theories.
The first is that, as aspirin reduces inflammation, it lowers the risk of cancer cells — which divide in part because of inflammation in the body — from spreading and mutating.
- The second theory involves how cancer cells “piggyback” on blood platelets, which help the blood to clot.
Aspirin thins the blood by making platelets less sticky, which may also make it harder for them to carry cancer cells, thereby preventing them from spreading.