Aspirin Linked to Reduction in Risk of Several Cancers of the Digestive Tract

Aspirin is associated with a reduction in the risk of developing several cancers of the digestive tract, including some that are almost invariably fatal, such as pancreatic and liver cancers.

The largest and most comprehensive analysis to date of the link between aspirin and digestive tract cancers, published in the leading cancer journal Annals of Oncology [1] today (Thursday), found reductions in the risk of these cancers of between 22% and 38%.

Aspirin has been linked to a reduction in the risk of bowel cancer for some time, and other, smaller analyses have found associations with cancers of the oesophagus (the food pipe or gullet) and stomach.

This analysis looked at evidence from 113 observational studies investigating cancers in the general population published up to 2019, of which 45 studies were on bowel cancer and included 156,000 cases. In addition to bowel cancer, the cancers investigated included those of the head and neck, oesophagus, stomach, the part of the stomach that connects to the oesophagus (gastric cardia), liver, gallbladder and bile ducts (hepato-biliary) and pancreas.

The researchers, led by Dr Cristina Bosetti (PhD), head of the Unit of Cancer Epidemiology at the Mario Negri Department of Oncology, Milan (Italy), found that regular use of aspirin, defined as taking at least one or two tablets a week, was associated with a significant reduction in the risk of developing all these cancers, apart from head and neck cancer.

Specifically, aspirin use was linked to 27% reduced risk of bowel cancer (45 studies), 33% reduced risk of oesophageal cancer (13 studies), 39% reduced risk of gastric cardia (ten studies), 36% reduced risk of stomach cancer (14 studies), 38% reduced risk of hepato-biliary cancers (five studies), and 22% reduced risk of pancreatic cancer (15 studies). Ten studies of head and neck cancer did not show a significant reduction in risk.

The senior author of the paper, Carlo La Vecchia (MD), Professor of Epidemiology at the School of Medicine, University of Milan, said: “There are about 175,000 deaths from bowel cancer predicted for 2020 in the EU, of which about 100,000 will be in people aged between 50 and 74. If we assume that regular use of aspirin increases from 25% to 50% in this age group, this would mean that between 5,000 to 7,000 deaths from bowel cancer and between 12,000 and 18,000 new cases could be avoided if further studies show that aspirin does indeed cause the reduction in cancer risk.

“Corresponding figures would be approximately 3,000 deaths each for oesophageal, stomach and pancreatic cancer, and 2,000 deaths from cancer of the liver. Given the unfavourable prognoses for these cancers, the number of new cases would be only slightly greater.”

The researchers also analysed the effect of aspirin dose and duration on bowel cancer. They looked at low dose (100 mg), regular (325 mg) and high dose (500 mg), combined with how many times a day, week or month it was taken.

Dr Bosetti said: “We found that the risk of cancer was reduced with increased dose; an aspirin dose between 75 and 100 mg a day was associated with a 10% reduction in a person’s risk of developing cancer compared to people not taking aspirin; a dose of 325 mg a day was associated with a 35% reduction, and a dose of 500 mg a day was associated with a 50% reduction in risk. However, the estimate for high dose aspirin was based on just a few studies and should be interpreted cautiously.

“Our findings on bowel cancer support the concept that higher aspirin doses are associated with a larger reduction in risk of the disease. However, the choice of dose should also take into consideration the potential risk of stomach bleeds, which increases with higher aspirin doses.

“Compared to people who did not take aspirin regularly, the risk of bowel cancer declined in regular aspirin users up to ten years. The risk was reduced by 4% after one year, 11% after three years, 19% after five years and 29% after ten years.”

Prof Carlo La Vecchia said: “These findings suggest there’s a beneficial effect of aspirin in the prevention of bowel and other cancers of the digestive tract. The results for bowel, oesophageal and pancreatic cancers are consistent with evidence from clinical trials on aspirin in the prevention of heart and blood vessel diseases.

“The findings for pancreatic and other digestive tract cancers may have implications for the prevention of these highly lethal diseases. For pancreatic cancer, we found that risk of the disease declined by 25% after five years among people who took aspirin regularly compared to those who did not.

“Taking aspirin for the prevention of bowel cancer, or any other cancers, should only be done in consultation with a doctor, who can take account of the person’s individual risk. This includes factors such as sex, age, a family history of a first-degree relative with the disease, and other risk factors. People who are at high risk of the disease are most likely to gain the greatest benefits from aspirin.”

In addition to stomach bleeds, the side effects of aspirin include bleeding in other parts of the body and, occasionally, haemorrhages.

As the study is based on observational studies, it can only show that aspirin is associated with a reduced risk, and biases or confounding factors may partly explain its results. Other limitations include the fact that in some studies information may not reflect changes in aspirin use over time; the people in the studies might not remember or report their aspirin use accurately; and most studies did not have data on other medications that might affect the association between aspirin and the risk of cancer.

Source: ESMO


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New Blood Test Can Detect Wide Range of Cancers

In a study involving thousands of participants, a new blood test detected more than 50 types of cancer as well as their location within the body with a high degree of accuracy, according to an international team of researchers led by Dana-Farber Cancer Institute and the Mayo Clinic.

The results, published online today by the Annals of Oncology, indicate that the test – which identified some particularly dangerous cancers that lack standard approaches to screening – can play a key role in early detection of cancer. Early detection can often be critical to successful treatment.

Developed by GRAIL, Inc., of Menlo Park, Calif., the test uses next-generation sequencing to analyze the arrangement of chemical units called methyl groups on the DNA of cancer cells. Adhering to specific sections of DNA, methyl groups help control whether genes are active or inactive. In cancer cells, the placement of methyl groups, or methylation pattern, is often markedly different from that of normal cells – to the extent that abnormal methylation patterns are even more characteristic of cancer cells than genetic mutations are. When tumor cells die, their DNA, with methyl groups firmly attached, empties into the blood, where it can be analyzed by the new test.

“Our previous work indicated that methylation-based tests outperform traditional DNA-sequencing approaches to detecting multiple forms of cancer in blood samples,” said Dana-Farber’s Geoffrey Oxnard, MD, co-lead author of the study with Minetta Liu, MD, of the Mayo Clinic. “The results of this study suggest that such assays could be a feasible way of screening people for a wide variety of cancers.”

In the study, investigators used the test to analyze cell-free DNA (DNA from normal and cancerous cells that had entered the bloodstream upon the cells’ death) in 6,689 blood samples, including 2,482 from people diagnosed with cancer and 4,207 from people without cancer. The samples from patients with cancer represented more than 50 cancer types, including breast, colorectal, esophageal, gallbladder, bladder, gastric, ovarian, head and neck, lung, lymphoid leukemia, multiple myeloma, and pancreatic cancer.

The overall specificity of the test was 99.3%, meaning that only 0.7% of the results incorrectly indicated that cancer was present. The sensitivity of the assay for 12 cancers that account for nearly two-thirds of U.S. cancer deaths was 67.3%, meaning the test could find the cancer two-thirds of the time but a third of the time the test returned a negative result. Within this group, the sensitivity was 39% for patients with stage I cancer, 69% for those with stage II, 83% for those with stage III, and 92% for those with stage IV. The stage I-III sensitivity across all 50 cancer types was 43.9%. When cancer was detected, the test correctly identified the organ or tissue where the cancer originated in more than 90% of cases – critical information for determining how the disease is diagnosed and managed.

“Our results show that this approach to testing cell-free DNA in blood can detect a broad range of cancer types at virtually any stage of the disease, with specificity and sensitivity approaching the level needed for population-level screening,” Oxnard obser

Source: Dana-Faber Cancer Institute

Study: Not All Processed Meat has the Same Cancer Risk

A study published in the journal Nutrients has questioned the World Health Organisation’s blanket classification of processed meat as carcinogenic.

Researchers say they have identified gaps between processed meat treated with nitrates and those that are not.

Dr Brian Green, Dr William Crowe and Professor Chris Elliott, from the Institute for Global Food Security (IGFS) at Queen’s University, Belfast, reviewed all recent, English-language studies into consumption of processed meat and cancer risk.

They said the results were inconclusive with around half the studies indicating a link with colorectal cancer (CRC).

The researchers added this may explain the appearance of contradictory claims in recent years.

However, when studies which only tested the consumption of processed meat containing sodium nitrite – a preservative used to extend shelf life and enhance colour – were isolated, scientists found evidence the link to CRC jumped from half to just under two-thirds (65%).

Dr Crowe said: “When we looked at nitrite-containing processed meat in isolation – which is the first time this has been done in a comprehensive study – the results were much clearer.”

In 2015 the WHO classified all processed meat as a carcinogen – including bacon, sausages and ham as well as continental European products like prosciutto and salami.

However, not all processed meat contains nitrates.

For example, British and Irish sausages are not processed with nitrites even though many of the European and US sausage equivalents are, such as frankfurters, pepperoni and chorizo.

Some retailers in the UK are already selling new types of bacon and ham that have been processed without nitrites.

The IGFS researchers now believe there is a need to define the health risk of both types of processed meat separately.

Co-author Professor Elliott, who carried out the UK Government’s inquiry into food safety after the horsemeat scandal, said the study brought more clarity to what has been a confusing area for the food industry and the public.

He explained: “Because there have been conflicting claims in the scientific community and the media about which types of meat may be carcinogenic, this study couldn’t have come at a better time.

“It brings much-needed rigour and clarity and points the way for further research in this area.”

Lead author Dr Green added: “It’s important we eat a healthy, balanced diet in line with the government’s ‘Eatwell Guide’.

“The current Department of Health guidance advises the public to consume no more than 70g of red or processed meat per day.

“That remains the guidance, but we hope that future research investigating the link between diet and CRC will consider each type of meat individually rather than grouping them together.

“Our findings clearly show that not all processed meats, for example, carry the same level of risk.”

The scientists say more research is needed before they can definitively prove causality regarding processed meat and cancer.

“But based on our study, which we believe provides the most thorough review of the evidence on nitrites to date, what we can confidently say is that a strong link exists between nitrite-containing processed meat, such as frankfurters, and CRC,” Dr Green concluded.

Source: Irish News

Omega-3 Supplements Do not Protect Against Cancer

Omega-3 fats do not protect against cancer – according to new research from the University of East Anglia.

Increased consumption of omega 3 fats is widely promoted globally because of a common belief that it will protect against, or even reverse, diseases such as cancer, heart attacks and stroke.

But two systematic reviews published today find that omega 3 supplements may slightly reduce coronary heart disease mortality and events, but slightly increase risk of prostate cancer. Both beneficial and harmful effects are small.

If 1,000 people took omega 3 supplements for around four years, three people would avoid dying from heart disease, six people would avoid a coronary event (such as a heart attack) and three extra people would develop prostate cancer.

The sister systematic reviews are published today in the British Journal of Cancer and the Cochrane Database of Systematic Reviews.

Omega 3 is a type of fat. Small amounts are essential for good health and can be found in the food that we eat including nuts and seeds and fatty fish, such as salmon.

Omega 3 fats are also readily available as over-the-counter supplements and they are widely bought and used.

The research team looked at 47 trials involving adults who didn’t have cancer, who were at increased risk of cancer, or had a previous cancer diagnosis, and 86 trials with evidence on cardiovascular events or deaths.

More than 100,000 participants were randomised to consume more long-chain omega-3 fats (fish oils), or maintain their usual intake, for at least a year for each of the reviews.

They studied the number of people who died, received a new diagnosis of cancer, heart attack or stroke and/or died of any of the diseases.

Lead author Dr Lee Hooper, from UEA’s Norwich Medical School, said: “Our previous research has shown that long-chain omega 3 supplements, including fish oils, do not protect against conditions such as anxiety, depression, stroke, diabetes or death.

“These large systematic reviews included information from many thousands of people over long periods. This large amount of information has clarified that if we take omega 3 supplements for several years we may very slightly reduce our risk of heart disease, but balance this with very slightly increasing our risk of some cancers. The overall effects on our health are minimal.

“The evidence on omega 3 mostly comes from trials of fish oil supplements, so health effects of oily fish, a rich source of long-chain omega 3, are unclear. Oily fish is a very nutritious food as part of a balanced diet, rich in protein and energy as well as important micronutrients such as selenium, iodine, vitamin D and calcium – it is much more than an omega 3 source.

“But we found that there is no demonstrable value in people taking omega 3 oil supplements for the prevention or treatment of cancer. In fact, we found that they may very slightly increase cancer risk, particularly for prostate cancer.

“However this risk is offset by a small protective effect on cardiovascular disease.

“Considering the environmental concerns about industrial fishing and the impact it is having on fish stocks and plastic pollution in the oceans, it seems unhelpful to continue to take fish oil tablets that give little or no benefit.”

Source: EurekAlert!

FDA Requests Market Withdrawal of Diet Drug Belviq Due to Cancer Risk

A clinical trial of the weight-loss drug Belviq (lorcaserin) shows an association with an increased risk of cancer, and the U.S. Food and Drug Administration is requesting that its maker withdraw the drug from the U.S. market.

Eisai Inc. has already “submitted a request to voluntarily withdraw the drug,” Dr. Janet Woodcock, who directs the FDA’s Center for Drug Evaluation and Research, noted in a statement issued Thursday.

Now, “we’re taking steps to notify the public,” she said, adding that “our review of the full clinical trial results shows that the potential risk of cancer associated with the drug outweighs the benefit of treatment.”

Woodcock said the FDA is advising that “patients should stop using the medication Belviq and Belviq XR [lorcaserin] and talk to their health care professionals about other treatment options for weight loss. Health care professionals should stop prescribing and dispensing Belviq and Belviq XR.”

The agency first announced that Belviq might have links to cancer in a communication issued Jan 15.

At the time, the FDA said “we cannot conclude that lorcaserin contributes to the cancer risk,” but “wanted to make the public aware of this potential risk. We are continuing to evaluate the clinical trial results and will communicate our final conclusions and recommendations when we have completed our review.”

That review appears to have led to calls for the voluntary withdrawal of the medication.

Belviq increases feelings of fullness so that people eat less. It’s available as a tablet (Belviq) and an extended-release tablet (Belviq XR).

According to the FDA, Belviq was first approved in 2012 as an add-on therapy to help aid weight loss, along with diet and exercise, in people who were obese or overweight.

Contingent on approval, the FDA ordered a randomized, placebo-controlled trial be conducted involving 12,000 people tracked for more than five years.

The trial wrapped up in June 2018, and the data showed that while 7.1% of those taking a “dummy” placebo developed cancer, that number rose to 7.7% among those taking Belviq.

“A range of cancer types was reported,” the FDA said. “Several different types of cancers occurred more frequently among patients treated with Belviq, including pancreatic, colorectal and lung cancer. During the trial, one additional cancer per 470 patients treated with the medication for one year was observed.”

People who have already taken Belviq should stop taking it, but “the FDA is not recommending special screening for patients who have taken Belviq,” Woodcock said.

Source: HealthDay