Fears colon cancers could be missed in young patients

Younger patients with incidentally detected adenomas present a growing problem for colonoscopic surveillance, an expert has warned, amid concerns about the potential rise of young-onset colorectal cancer (CRC).

Associate Professor Alan Moss, Director of Endoscopy at Western Health, Victoria, said there was a lack of data on what transpires over time for average risk patients too young for bowel cancer screening programs (age <50) who had incidental colorectal adenomas detected and removed.

“The classic cases are a 35-year old woman with abdominal discomfort, bloating, altered bowel habit and iron deficiency in whom a colonoscopy reveals no sign of colitis nor malignancy but does detect incidental polyps; or a 40-year-old man with rectal bleeding and altered bowel habit in whom colonoscopy identified haemorrhoids as the cause of bleeding as well as incidental polyps,” he told doctorportal.

“These adenomatous polyps are removed at colonoscopy, but then we don’t know whether these patients are at the same risk of interval colorectal cancer as older patients, or whether their young age at presentation means they’ve got a significantly stronger predisposition to colonic polyp formation and greater potential for more rapid progression to colorectal cancer,” he said.

As a result, there was uncertainty about the ideal timing for subsequent surveillance colonoscopies to avoid interval colorectal cancer.

Associate Professor Moss said: “We don’t want to over-scope patients, but we also don’t want to miss the boat in these younger patients.”

Study finds that endoscopists prefer more intensive surveillance

Associate Professor Moss was commenting following the publication of his editorial in Gastrointestinal Endoscopy regarding a US study that found significant variation in endoscopists’ surveillance decisions for young patients with sporadic incidentally detected colorectal adenomas.

The study at a single US hospital focused on 141 patients under the age of 40 who had no known propensity for CRC before neoplastic polyps were discovered at an index colonoscopy.

While there was significant variation in endoscopists’ recommendations, in most cases endoscopists recommended repeat colonoscopy in three to five years. This was consistent with the recommendations of the main US colonoscopy surveillance guidelines, known as the US Multi-Society Task Force (MSTF) on colorectal cancer, which have been validated for patients over the age of 50.

However, when endoscopists in the study varied from the MSTF guidelines, it was to recommend a more aggressive surveillance strategy. The study showed that for patients with findings of high-risk, non-polypoid and serrated neoplasia, endoscopists regularly recommended shorter surveillance intervals than the MSTF guidelines propose for these polyps.

Young patients may under-estimate risk

Strikingly, the study also found that few young patients (24.7%) were compliant with their doctor’s repeat colonoscopy recommendations.

Associate Professor Moss commented in his editorial that younger patients might not appreciate their potential risk of developing colorectal cancer, as the compliance rates were substantially lower than shown for older patients in other research.

“It draws attention to the need for endoscopists to work particularly hard to educate young patients about the adenoma-to-carcinoma sequence, the important role of colonoscopy and polypectomy in altering the natural history of CRC, and the importance of adhering to surveillance recommendations,” he wrote.

The time was ripe for well-designed, multicentre, long-term follow-up studies of younger patients with adenomas, he argued.

In the meantime, he suggested Australian doctors adhere to the Cancer Council of Australia Colonoscopy Surveillance Guidelines.

Individual cases must be considered carefully, paying particular attention to cases of multiple polyps or advanced polyps, Associate Professor Moss wrote.

“In our own colonoscopy practice, we are increasingly being referred young patients for EMR (endoscopic mucosal resection) of an incidentally detected large sessile serrated adenoma/polyp,” he wrote.

“These young patients usually have no relevant family history and they do not meet the criteria for serrated polyposis syndrome at that stage. However with further surveillance colonoscopies over subsequent years, some experience sufficient serrated polyps in size and number to meet the diagnostic criteria for Serrated Polyposis Syndrome.”

Young-onset colorectal cancer rising?

The American Cancer Society (ACS) this year updated guidelines for those at average risk of bowel cancer to begin screening from age 45 (previously age 50).

It came on the back of a major analysis which showed people born in 1990 had double the risk of colon cancer and quadruple the risk of rectal cancer compared to those born in 1950.

However it is unclear whether the same trend is occurring in Australia. A study in the Medical Journal of Australia found the incidence of young-onset colorectal cancer did not increase in NSW during 2001–2008, although cases in younger patients tended to be more advanced at presentation than cases in older patients.

Australian guidance

Dr Karen Barclay, Senior Lecturer in Surgery at the University of Melbourne is the author of the Cancer Council Australia’s algorithm on Colonoscopic Surveillance of Adenomas. She said the tool – which recommends colonoscopy at 5 years for low risk cases, and 3 years for high-risk cases – should be used for patients of all ages.

“There needs to be an appropriate reason for recommendation of earlier surveillance as colonoscopy has risk and financial cost to the patient and the system. Younger patients are at risk of having a substantial number of colonoscopies over a lifetime if surveillance is too frequent and balance must be obtained,” Dr Barclay told doctor portal.

She added: “Clinicians advising young people should emphasise preventive strategies.”

Dr Barclay also directed doctors to national guidelines on managing patients with serrated polyposis syndrome. Colonoscopy every 1 to 3 years is recommended in this cohort.

Push to reduce unnecessary colonoscopies

A new Colonoscopy Clinical Care Standard has been launched by the Australian Commission on Safety and Quality in Health Care and will benefit millions of Australians seeking treatment.

It is the first nationally agreed standard of care for patients undergoing a colonoscopy.

The number of Australian who have a colonoscopy each year is approaching one million. Despite it being frequently performed, it is a complex medical procedure and should only be offered if the benefits outweigh the risks.

Undergoing the procedure unnecessarily doesn’t make sense and may extend the wait time for those who do need it, according to the new standard.

In launching the new standard in Brisbane during Australian Gastroenterology Week in September, the Commission said patients with a positive bowel cancer screening result should consult their general practitioner to discuss further investigation. In many cases this will be a colonoscopy.

The procedure examines the large bowel (colon) to diagnose and treat a range of bowel diseases including bowel cancer, the second most common cancer diagnosed in both men and women in Australia. Bowel cancer is expected to claim more than 4,000 lives in Australia in 2018.

The Commission’s Clinical Director Professor Anne Duggan said the new standard offers guidance to patients, clinicians and health services at each stage of a colonoscopy, with the goal of ensuring high-quality and timely colonoscopies for patients who need them. The standard will also help to reduce the number of unnecessary colonoscopies being carried out.

“The Commission’s Australian Atlas of Healthcare Variation 2015 found stark differences across the country in rates of colonoscopies being performed, with some areas having colonoscopy rates 30 times higher than others,” Professor Duggan said.

“Colonoscopy rates were significantly higher in capital cities and lower in remote areas. In major cities, rates were lower in areas of low socioeconomic status. The clinical care standard supports clinician certification and recertification as requirements for colonoscopy services, and will bring increased rigour to the procedure and shine a light on when and how these procedures are done.

“We asked experts in colonoscopy about how to look after people in the best possible way and used this information to develop guidelines for everyone involved.”

Gastroenterological Society of Australia (GESA) spokesman Dr Iain Skinner is a colorectal surgeon and advanced colonoscopist who co-chaired the Commission’s working group that developed the new standard. He said the guidelines were much needed.

“The clinical care standard further enhances care, focusing on bowel preparation, sedation, the colonoscopy and recovery. The standard also clarifies appropriate use of the procedure based on evidence,” Dr Skinner said.

“This is an advanced procedure and we don’t want it being performed unnecessarily. Fewer unnecessary colonoscopies will free up access to more timely colonoscopies for those who are at moderate or high risk, such as those with a history of polyps or a significant family history of bowel cancer, or those who return a positive bowel screening test.”

The Colonoscopy Clinical Care Standard and separate fact sheets for consumers and clinicians can be found on the Commission’s website at: https://www.safetyandquality.gov.au/our-work/clinical-care-standards/colonoscopy-clinical-care-standard/

Probiotics: a first look at what’s going on in the gut

For the first time researchers have taken samples from inside people’s guts to find out how much probiotics change the composition of microbes and the chemical compounds they produce. And they found that the effect of probiotics depends on the bacteria that are already present in the gut.

Probiotics are live microbes – mostly bacteria – that when eaten in the right quantity can provide health benefits. They can be included in foods, such as yoghurt, or taken as dietary supplements or added to drugs.

For a microbe to be considered a probiotic it must survive the acid environment of the stomach and it must boost the number of good bacteria in the gut. Also, probiotic microbes may grow (make “colonies”) by attaching to tiny hairs that exist in the intestines. They may produce chemical compounds that kill disease-causing bugs, such as diarrhoea viruses, or they may produce certain substances, such as vitamins.

We now know that the microbes in our guts have important effects on our health. They can reduce inflammation, help us lose weight , and reduce the risk of diabetes and heart disease. So we want to know if probiotics change the composition of our gut microbes to help improve our health.

Better than stool samples

So far, all that we know about the changes that probiotics make to the types of microbes in our gut comes from scientists analysing the bacteria in stool samples of people who have taken probiotics. But this won’t tell us if the microbes are forming colonies or what is really happening inside the digestive tract. To answer these questions, scientists in Israel have taken samples from different regions of the guts of people by putting a tube inside their bodies to measure the bacteria.

The microbes measured in stool samples are more like those from the lower part of the gut than those higher up in the gut, closer to the small bowel. Their data show that the bacteria measured from poo aren’t very representative of what goes on in the whole gut.

The researchers also found that a lot of the good microbes that were eaten as probiotics did not attach to the tiny hairs in the gut but ended up in the poo. However, the amounts of these bacteria in faeces was not representative of how many good bacteria actually managed to stay alive inside the person’s gut.

Using very sophisticated methods they were able to confirm that probiotic supplements change the chemical compounds that are produced in the gut, compared with people who didn’t take probiotics.

The most important finding to come out of this study is that the response to probiotics changes between individuals and that the health impact will depend on the bacteria that are already present in the gut.

The authors conclude that the one-size-fits-all approach to probiotics is not ideal and that it would be better to tailor probiotics to individuals, depending both on the health benefits they need and on the microbes already living in their guts.

Worth taking?

Are probiotics any good and is it worth taking them? The short answer is yes, but they could be better.

We have recently searched the scientific literature and found 313 good quality clinical studies (randomised controlled trials) involving almost 50,000 people where researchers had investigated the health benefits of taking probiotics or taking a placebo. Our analysis showed that taking probiotics can help prevent diarrhoea, bronchitis and eczema. They also seem to improve heart disease risk and reduce substances in the blood that have to do with inflammation.

So, although most probiotics don’t permanently change the microbe composition of the gut, it seems that probiotics can affect health. They may be doing so by improving our immune system or producing beneficial chemicals. And if it becomes possible to tailor probiotics for an individual’s characteristic then probiotics may actually be much more effective than they are right now.

Ana Valdes, Associate Professor and Reader, University of Nottingham

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Mixed reviews for direct-to-consumer gut microbiome test

Leading gastroenterologists have warned against a new direct-to-consumer test that promises to reveal the good and bad bacteria in a person’s gut, despite high-profile endorsements of the technology.

Cervical cancer vaccine pioneer, Professor Ian Frazer, is director of the start-up company Microba, which is inviting Australians to pay $349 for metagenomic sequencing of their gut biome.

The mail-order faecal swab kit was launched in July at an event MC’d by renowned dietitian, Dr Joanna McMillan, who in February presented an episode of ABC TV’s Catalyst program on how DNA testing was “driving the gut revolution”.

Microba customers are promised personalised reports based on their test results, including data on their microbiome’s potential to digest carbohydrates, protein and fat, and to produce essential vitamins such as folate. They are also offered personalised dietary information.

Dr Alena Pribyl, Senior Scientist at Microba told doctorportal: “When you eat food, most of it is going to be processed by digestive enzymes in the stomach and absorbed in the small intestine, and then what can’t be digested – fibre and excess protein – passes to the large intestine where it’s available for microbes to digest. These microbes produce their own enzymes.”

She continued: “What our test can do is look at different genes in each of those microbes that can break down fibre and protein, and see what enzymes the bacteria can produce.”

Microba has stressed that its test is not diagnostic, but says on its website: “Once you have the clear picture of your gut, you can make changes to improve wellbeing.”

For instance, Dr Pribyl said if the test showed a low potential for the gut microbiome to produce butyrate people might respond by increasing their intake of fibre, in particular resistant starch.

Over-interpreting the results

However leading gastroenterologists say interpreting and responding to the test results is not straightforward, nor evidence-based. Many have criticised the move to offer testing direct-to-consumers.

Professor Peter Gibson at Monash University, whose discoveries about the low FODMAP Diet have transformed the management of irritable bowel syndrome, told doctorportal the technology offered exciting research possibilities but had no present clinical utility.

“This [test] has no use since we do not know what the results mean in terms of therapy, diet, etcetera… Acting upon the results is not evidence-based,” he said. “While we still debate what ‘dysbiosis’ is, what is cause and what is effect, and what it all means, these tests should not be used in clinical practice.”

He added: “The results are likely to be over-interpreted, and even more so by consumers. It may induce anxiety and do more harm than good.”

Professor Emad El-Omar, Editor In Chief of the journal GUT said few gastroenterologists would use the test as “hardly anyone would be able to interpret, with any certainty, what the results mean.”

“Until we have some evidence that certain microbiota signatures are predictive of disease course, its treatment or its response to manipulation, it is not wise to raise hopes too high or indeed create anxiety if the analyses show a less than favourable result.”

Professor El-Omar added: “I have a lot of respect for the people that developed this test but I caution against its use as a commercial test ready for the big time. We are not ready and everyone knows this. Let’s do the hard work and do some clinical trials and proper clinical research.”

Testing may be irrelevant

Nutritionist Dr Rosemary Stanton said patients did not need to know the composition of their gut biome to make lifestyle changes that would improve their gut health.

“We already know that healthy gut bacteria are important. It’s one of the reasons why the dietary guidelines recommend consuming more healthy plant foods, less junk food and only modest amounts of red meat,” she said.

“If people have digestive problems, they should see their GP. That is then the best person to decide whether such tests are appropriate,” she said.

“I do not recommend encouraging self-diagnosis – especially if it involves expensive tests which may be irrelevant for the particular problem. If the tests are useful, they should be reserved for those who really need them.”

For the curious

Dr Pribyl defended the company’s decision to offer the test direct-to-consumers.

“A lot of overseas companies are already offering gut biome testing direct-to-consumers but are providing over-extrapolated results from low-resolution data,” she said. “There has been so much media hype, we wanted to provide a product backed up by evidence.”

Other tests on the market are based on sequencing the 16S rRNA gene only, whereas Microba sequences the whole genome of the lower intestine’s microbiome.

Dr Pribyl added: “We are not recommending patients do this test instead of seeing a healthcare professional. This is just for people who are curious about what is happening in their gut or for healthcare professionals to use with complex patients.”

Customers also have the option of sharing their health data to assist further research.

Around 3000 kits have been sold since July, Dr Pribyl said, “to a mix of people – probably some ‘worried well’, but also to specialists including gastroenterologists and allied health practitioners.”

Microba is offering a free course for healthcare professionals about the gut biome. The company is also currently working on a product specifically for healthcare professionals, however, Dr Pribyl said regulatory hurdles meant it would be a few years before this was available.

Professor Ian Frazer was not available for an interview but said in a statement Microba had a long- term commitment to advancing the current growing knowledge of how the constituents of the gut microbiome can impact on human health.

“This knowledge will determine how and when we should incorporate the new technology of metagenomic classification of mixed microbial environments into routine patient care,” he said.

Professor Frazer is a board member and shareholder in Microba and comments attributed to him are his own, and should not be held to be representing the views of any employer.

Probiotics and prebiotics – is it safe to use them to treat disease?

The link between gut microbes and health is now well established. As a result, researchers have been investigating the effects of probiotics, prebiotics and synbiotics on various diseases. Worryingly, though, they haven’t been reporting on the safety of these treatments – as one would for a drug trial.

A new review of 384 randomised controlled trials, published in Annals of Internal Medicine, found that information on the safety of these supplements is either lacking or not reported.

More than a quarter of the trials (28%) didn’t report any harms data, and safety results weren’t reported in 37% of the studies. Of the studies that did mention harms, 37% used only “generic statements” to describe adverse events, and 16% used “inadequate metrics”, according to the researchers.

So what?

But what’s all the fuss about, you might wonder? Aren’t these all natural products that are available in supermarkets and health food shops? Indeed, the two main families of probiotic bacteria, Lactobacillus and Bifidobacterium, are found in many fermented foods, such as sauerkraut, kimchi and yogurt.

Probiotic bacteria are found in fermented foods.
marekuliasz/Shutterstock.com

Prebiotics don’t even contain bacteria, they are merely food on which probiotics feast. They are fibres that can’t be absorbed or broken down by the body, but they nourish friendly bacteria, particularly the Bifidobacteria genus. Bananas, onions, garlic and legumes are natural prebiotic sources.

Synbiotics are foods or supplements that combine probiotics and prebiotics.

Although these products all sound harmless, and may not do any harm to a healthy person, a good clinical trial should always report adverse events (harms). Trials involving these supplements are often in patients who are severely ill or physically vulnerable, such as preterm babies, so the effect of probiotics, prebiotics or synbiotics might be different in these patients.

Several case studies have reported an increased risk of fungaemia – the presence of fungi or yeasts in the blood – in people treated with probiotics. This complication is rare and it tends to happen in people with suppressed immune systems, but it is serious.

Probiotics can have serious adverse effects in other vulnerable groups. For example, a 24-year-old woman, who was administered probiotics before aortic valve replacement surgery, developed sepsis.

In the past few years, probiotic use in hospitals has increased greatly. However, there is growing evidence that the use of probiotics in patients with organ failure, compromised immune systems and those whose intestinal barrier mechanisms are impaired increases the risk of infection.

A trial in the Netherlands, designed to see whether probiotics (administered as Yakult) could reduce the incidence of infectious complications in patients with severe acute pancreatitis, ended up being investigated after 15 patients died unexpectedly.

A few trials involving probiotics have reported on adverse events in vulnerable groups, such as the elderly, and found no serious harms. But these trials tend to have very low participant numbers, reducing the significance of the claims.

It is clear that there is an urgent need for standard safety and administration protocols for probiotics in clinical trials.

Amreen Bashir, Lecturer in Biomedical Science, Aston University

This article was originally published on The Conversation. Read the original article.

Fears over colonoscopy wait-list blowout

Australians with a positive screen for bowel cancer are unlikely to get a diagnostic colonoscopy within the recommended timeframe, according to a new report.

Figures from the AIHW’s National Bowel Cancer Screening Program: monitoring report 2018 show that there is only one state or territory – Victoria – where 90% of patients aged between 50 and 74 get a colonoscopy within 120 days of a positive FOBT test. In Australia’s most populous state, New South Wales, patients are likely to wait an extra month on top of the recommended 120 days, while in South Australia the wait is 182 days. Research has shown that patients who wait for more than 120 days have statistically poorer outcomes.

Nor is the trend moving in the right direction. In Victoria and ACT, waiting times are slightly down on the previous year, but in all other states and territories they are up, in some cases substantially. Waiting times in Tasmania and the Northern Territory have risen by around a month year-on-year. In the Top End, positively screened patients now wait 197 days for a colonoscopy, more than two months longer than the recommended period.

“People who receive a positive screen or experience bowel cancer symptoms must receive a timely follow-up colonoscopy, or the opportunity for early detection is lost,” says Sydney-based colorectal surgeon and Bowel Cancer Australia spokesperson Associate Professor Graham Newstead.

“We know 90% of bowel cancer cases can be successfully treated if detected early,” he adds.

The problem is likely to be further exacerbated as the national screening program expands and efforts are ramped up to increase participation. By 2021, demand for colonoscopies is set to exceed 1 million per year, it has been estimated.

Meanwhile, new research published in Australian Journal of General Practice suggests that a significant proportion of the colonoscopies that are carried out are actually performed on the wrong people.

Around 80,000 of the 700,000 colonoscopies performed in 2012-213 were on people over 50 with only an average risk of bowel cancer. The study authors, led by Professor Jon Emery of the University of Melbourne, say their modeling shows these people are being overscreened and should be given an FOBT test instead. That would free up capacity for the 29,000 people who are at greater risk and who are not getting colonoscopies, the authors say.

“The large variations in colonoscopy rates in Australia suggest that many people at average risk of colorectal cancer are choosing to have colonoscopy as a screening test, mostly through GP referrals to private endoscopists and funded, at least in part, through MBS payments,” the authors write.

Professor Emery says colonoscopic overscreening can be managed by GPs through correct referral pathways depending on the patient’s risk of bowel cancer.

“It is alarming that so many Australian patients are undergoing unnecessary colonoscopies and potentially putting other patients at risk of delayed diagnosis,” Professor Emery says.

Currently, over 40% of colorectal cancers are diagnosed at Stage 3 or 4 in Australia, which along with New Zealand has the highest rate of colorectal cancer in the world.

You can access the full study here.

The link between acid suppressants and allergy

The evidence is mounting that the dramatic increase in kids’ allergies over the past couple of decades could have something to do with medication-induced disturbances in the intestinal microbiome.

The latest evidence for this hypothesis comes from a large, retrospective US study published this week in JAMA, involving nearly 800,000 children under six months old. The researchers cross-checked the use of H2RA and PPI acid suppressants, as well as antibiotics, with the subsequent diagnosis of allergic diseases in this cohort.

Infants in the cohort who were prescribed acid suppressants were more than twice as likely to develop food allergies in later childhood, with peanut and cow’s milk allergies being the most common. They were also 70-80% more likely to develop an allergy to a medication, and 45-50% more likely to be hospitalised for anaphylaxis. Rates were also higher for allergic rhinitis and asthma.

Infants prescribed antibiotics also had higher allergy rates: they had double the risk of asthma, a 75% greater risk for allergic rhinitis and a 41% higher risk for anaphylaxis.

“Acid-suppressive medications and antibiotics should be used during infancy only in situations of clear clinical benefit,” the researchers conclude.

They caution that as the study was observational, a causal link cannot be demonstrated. But while it is possible acid-suppressants or antibiotics were given for misdiagnosed allergic diseases, the authors say this is very unlikely to explain all the findings.

They say what is more likely is that acid-suppressants or antibiotics enhance the development of allergies by altering the makeup of the microbiome. They point to increasing evidence that healthy flora in the gut modulate immune responses and augment regulatory T-cell populations, possibly by the production of short-chain fatty acids. Getting the right microbial balance in early life seems especially important, with mouse studies showing antibiotic-induced dysbiosis causing allergies in neonatal mice but not in adult mice.

The study showed a stronger risk of food allergies with acid-suppressing drugs than with antibiotics, which might be because the former increases sensitisation to ingested antigens by decreasing protein breakdown in the stomach, the authors say. In addition, H2RAs may have a direct effect on the immune system, as histamine is increasingly recognised as having a role in modulating immune system function.

In current paediatric practice, acid suppressants are generally considered safe and are commonly prescribed for infants who have a regurgitation problem or are fussy. Studies like the current one may prompt a rethink in prescribing patterns, particularly given that gastric regurgitation in infants is not a disease but a developmentally normal process.

Recent research has found little clinical benefit in the use of H2RAs and PPIs in infants, and paediatricians are increasingly advising against overprescription of these drugs. They should be prescribed “only in situations of clear benefit”, the study authors warn.

You can access the full study here.

Bowel cancer and the key to prompt colonoscopy referral

If Australia’s National Bowel Cancer Screening Program can reach and maintain a 60% participation rate in the next couple of years, 84,000 premature bowel cancer deaths could be avoided by 2040. GPs will be pivotal to achieving this goal, as will greater use of bowel cancer guidelines throughout the health system.

The mortality reduction projections were published as part of a review of clinical practice guidelines for the prevention, detection and management of colorectal cancer in Australia, approved by the National Health and Medical Research Council in October 2017.

With so much to gain, it’s timely to emphasise the life-saving benefits of the NBCSP and to highlight the new guidelines’ recommendation for prompt colonoscopy referral:

“Colonoscopy should be performed as promptly as possible after a positive iFOBT to minimise the risk of psychological harm, although there is no evidence that prognosis is worsened within 120 days if cancer is present.”

The advice is the same for the symptomatic patient, as both recommendations drew on the same systematic review evidence. The reference to “120 days” was based on an analysis of nine cohort studies that met the systematic review inclusion criteria and were deemed relevant to the clinical question.

The finding, however, is not a recommendation to wait 120 days. The guidelines are explicit in recommending patients with a positive iFOBT or symptoms are referred for investigation “as promptly as possible”. The 120 days does however draw a line in the sand, based on evidence, and states that any delay beyond this could have an adverse clinical outcome.

Waiting for a colonoscopy after a positive iFOBT or presentation with symptoms is likely to cause anxiety in some patients and could cause some to drop out of the screening program. So it is critical that such patients are investigated as promptly as possible.

Which brings us to the problem of colonoscopy waiting times.

Around 1 million colonoscopies are performed in Australia each year. In 2015 (the most recent data), only 29,000 colonoscopies were conducted for people who had tested positive for iFOBT through the NBCSP – about 3% of total colonoscopies.

Even allowing for people who screen with iFOBT outside the program, and for other priority patients (those with symptoms or family history), we can still assume tens of thousands of average-risk people are screening with colonoscopy. Is it any wonder there are reports of pressures on colonoscopy waiting times, when there is such widespread inappropriate use of colonoscopy as a first-line screening tool?

The best way to free up colonoscopy services for people with the highest need is for more average-risk Australians to screen with iFOBT.

The first recommendation in the population screening chapter of the colorectal cancer guidelines is for iFOBT to be used “as the screening modality for the detection of colorectal cancer in the average-risk population”. iFOBT has a sensitivity rate within the screening program of 83%, was shown in pilot studies to be acceptable to the population and is a fraction of the cost of colonoscopy – and for NBCSP participants, iFOBT is free.

Evidence shows the NBCSP has the potential to prevent more premature cancer deaths in the short, medium and long term than any other public health intervention introduced in Australia. The benefits increase in step with the rate of program participation.

Based on current evidence of clinical and cost benefit, and overall feasibility, there is no other way to save 84,000 Australians from a premature bowel cancer death within 20 years. We should be promoting what promises to be one of the world’s great cancer control initiatives – and prioritising healthcare services to help ensure it reaches its potential.

If Australia has capacity to perform 1 million colonoscopies in a year, surely we have capacity to ensure people who test positive for iFOBT or have bowel cancer symptoms are investigated within a matter of weeks. We need more clinicians supporting the NBCSP and adhering to guidelines to help ensure limited healthcare resources are prioritised for those who need them most on a population basis.

Professor Tim Price is a medical oncologist and the chair of the multidisciplinary expert management group that oversaw the development of the NHMRC-approved clinical practice guidelines for the prevention, detection and management of colorectal cancer.

Does faecal transplant work in irritable bowel disease?

One of the medical miracle stories of the past decade has been the astonishing efficacy of faecal microbiota transplantation (FMT) – colloquially known as poo transplants – for the treatment of hospital-acquired Clostridium difficile infections. Previously, patients usually endured several cycles of antibiotics to treat the condition – cycles that often turned vicious, as the antibiotics tended to reduce microbiome diversity, which in turn encouraged the return of C. difficile. But all this changed when a landmark study that found FMT – previously considered something of a quack form of medicine – had a success rate of over 90% in clearing the infection.

The discovery has focused attention on the importance of the intestinal microbiome in a number of diseases, particularly those with an autoimmune component, such as inflammatory bowel disease. There have been several trials of FMT for ulcerative colitis so far, with mixed but promising results. At the wilder end of the spectrum, researchers have talked up the possibility of FMT in diseases as disparate as rheumatoid arthritis, asthma, multiple sclerosis and autism.

What of irritable bowel syndrome, thought to affect over 10% of the population? It is notoriously difficult to treat, probably due to its multifactorial pathology. Many researchers in the field do think that targeting microbiota with FMT may prove effective, particularly given the strong evidence of the role of bacterial, viral and parasitic infections in triggering IBS, along with the transient relief of symptoms felt by many patients after antibiotics. But serious research is only at its initial stages. In fact, the first truly randomised, double-blind, placebo-controlled trial of FMT in moderate-to-severe IBS was only published earlier this year. That trial of 90 participants found a significant effect on IBS severity at three months, although not at 12 months, with no serious adverse effects reported.

A systematic review published this month has collated the results of 48 IBS patients across several conference abstracts and case reports, finding an improvement with FMT in 58% of cases. Two of the studies mapped the microbiome before and after FMT, finding greater diversity of bacterial species after treatment. The review authors say that although methodological differences between the studies make it hard to verify findings, they do lay the groundwork for further research in the area. Currently, eight randomised studies of FMT/IBS are registered on clinicaltralis.gov. Several of these include sequencing the microbiome before and after treatment, which should offer clues as to the real effects of FMT in this condition and where to go next.

One interesting mouse study involved colonising mouse guts with the faecal content of either healthy patients or those with diarrhoea-predominant IBS (IBS-D) with anxiety. The mice with IBS faecal content had faster gastrointestinal transit time and higher colonic paracellular permeability than the other mice, pointing to the importance of the microbiome in the disease. Oddly enough, the mice with material from patients with IBS-D with anxiety themselves showed more signs of anxiety-like behaviour in the laboratory environment.

Concern over new bowel cancer guidelines

New NHMRC guidelines that allow for considerably longer waits for colonoscopies in people suspected of colorectal cancer have been met with strong criticism from Bowel Cancer Australia.

The guidelines, published this month, say that for patients with symptoms suggestive of colorectal cancer, the total time from first presentation to diagnostic colonoscopy should be no more than 120 days. This is a significant change from previous guidelines, which recommended no more than 30 days after a positive FOBT test or visit to a GP with symptoms.

“We’ve got evidence to show that if you go beyond 30 days, you increase the risk, and if you run it out to 120 days, the cure rate will be lower,” says Bowel Cancer Australia’s Director, Associate Professor Graham Newstead, a Sydney-based colorectal surgeon.

He notes that if a cancer is caught early at the T1 stage, the cure rate is 98%.

“But if you wait until it’s a T2 cancer, the scale drops down and by the time you have metastasis you’re down to 40%.”

Dr Newstead says that the FOBT test is far from perfect and misses around 30% of cancers. He adds that while it’s understandable there aren’t resources for a colonoscopy-based national screening program, “if you’re going to use FOBT, then you simply can’t start extending the period of time to colonoscopy for people with a positive test”.

But the larger issue, he says, is that recommended times to colonoscopy are rarely met in Australia anyway.

“Around 90% of patients with positive FOBT wait between 116 to 181 days. It’s all very well to suddenly shift the goalposts and say 120 is OK, but 90% of patients are still somewhere equal to or beyond that date.”

The UK, with its overstretched National Health Service, still manages to do much better than Australia, Dr Newstead says, with over 90% of patients getting a colonoscopy after a positive FOBT test within a mandated 42 days.

Bowel Cancer Australia Chief Executive Julien Wiggins says that some people involved in developing guidelines have expressed concerns that the extended threshold de-emphasises the need for prompt evaluation.

“What is needed is a colonoscopy wait-time guarantee,” he says, “complete with public wait-time recording, reporting and adequate resourcing of colonoscopy.”

While the guideline authors say their new 120-day recommendation is evidence-based, Dr Newstead says two recent studies – one in Cancer Epidemiology, Biomarkers and Prevention, and another in Clinical Gastroenterology and Hepatology – go against the recommendation and support colonoscopy within 30 days of a positive FOBT.

He says he suspects the real reason for the change is a question of resource allocation and a desire to take some of the pressure off waiting lists.

Regardless of the increased risk, delaying colonoscopy adds considerably to the stress levels of already worried patients, he notes.

“Performing colonoscopy as promptly as possible minimises the risk of psychological harm in people experiencing symptoms or those with a positive screen awaiting investigation,” he says.

You can access the new guidelines here.