Exercise and Breast Cancer

I was alerted today to an interesting new paper in the Journal of the National Cancer Institute that looked at the effect of exercise on tumour blood supply and the response to chemotherapy in breast cancer. Now this is a topic which is worth paying attention to – there is lots of evidence that daily exercise can reduce breast cancer recurrence, have positive effects on physical status and may even improve overall survival in women with breast cancer. With that in mind, what does this new paper tell us?

Firstly, it’s important to note that this isn’t a study in people – this is a study in mice. But these are mice with intact immune systems and they are bearing mouse tumours. It means that although this is an animal model we can trust the evidence a bit more than we can when dealing with immune deficient mice implanted with human tumours. Secondly we should note that these mice were not forced to do exercise – so there was no additional stress involved and there were no enforced amounts of exercise that had to be performed. Basically the mice were given an environment which gave them an exercise wheel they could use, whereas the comparison group didn’t have the opportunity to exercise. Finally, some of the mice had ER+ and some ER- tumours, matching human tumours in hormone responsive and non-responsive sub-types.

What the study showed was that the mice doing the exercise had a reduced the tumour growth rate, an increased the rate of cancer cell death (apoptosis), increased the maturity of the tumour blood vessels, increased tumour blood flow and reduced the areas that were starved of oxygen (hypoxia). These are all things which are positive and which we definitely would want to achieve clinically. Basically these results show that exercise normalises the tumour blood supply. This is a good thing.

Normally the tumour blood supply is chaotic – vessels are immature, leaky, misconnected. This chaotic blood supply has a number of downsides. Firstly it means that the drugs we give cancer patients to kill the tumour often don’t make it into the interior of the tumour – not good because if they don’t in they won’t work. Secondly the chaos causes areas of the tumour to become starved of oxygen and nutrients – this in turn causes the cancer cells to become more aggressive and dangerous as they adapt to these harsh conditions.

So, normalising the blood supply means that tumours are not forced to become more aggressive and, as we see in these results, this can lead to a slower growth rate. It also means that when drugs are administered they can make it into a greater portion of the tumour. And this is where the second lot of results come in. Mice treated with the chemotherapy drug cyclophosphamide had greater response if they were exercising compared to the sedentary mice. Interestingly, mice who did exercise alone (no chemo) showed a similar response to mice treated with chemo alone. But the best response came from mice who had chemo and did exercise.

These are positive results but we do have to keep in mind that this is in mice. However, it backs up what we know from evidence in humans and suggests reasons for why we’ve seen these results. The take home from this is that exercise has a positive effect in breast cancer – and most likely in other cancers too. It doesn’t have to be running a marathon every week either – a study in women with breast cancer back in 2005 found that walking at an average pace for 3 – 5 hours per week had positive effects on survival.

Organic Food and Cancer Risk

There is a theory popular in certain alternative and complementary medicine circles that cancer is caused by environmental toxins, radiation, microwaves, mobile phones and just about every modern convenience in the household. While there's little evidence for any of this, the idea that there are 'chemicals' lurking in the environment has become common-place, particularly when it comes to food. Hence one of the most common questions from newly diagnosed cancer patients: should I switch to an organic diet? There are enough people out there pushing the idea that 'organic' food is healthier than conventionally grown food, so it should be no surprise that people naturally feel that food grown 'without chemicals' will help them in the fight against cancer. After all conventional crops depend on 'chemicals' and organic food doesn't. And we all know that chemicals, in this case mainly pesticides, are bad for you. Therefore organic food should be healthier, and the strong growth in organic food sales in the last ten or fifteen years shows how popular opinion has accepted this assertion. 

However, the results of a new UK study that looked at cancer risk and the consumption of organic food seems to suggest that popular opinion is pretty much wrong in this case (http://www.nature.com/bjc/journal/v110/n9/full/bjc2014148a.html). While organic food and alternative medicine advocates have pushed organics as a way of reducing cancer risk, the study shows that it makes little difference one way or another. The study in question appears in the British Journal of Cancer and is by Oxford University cancer epidemiologist Dr Kathryn Bradbury and co-workers. Part of the Million Women Study funded by Cancer Research UK and the Medical Research Council, this particular bit of research tracked 623 080 middle-aged British women for almost ten years and looked at their pattern of organic food consumption and the incidence of sixteen different cancer types, as well as overall cancer incidence.

Based on their reported eating habits the women were put into three groups: never, sometimes, or usually/always eating organic food. The headline result showed that eating organic was not associated with overall cancer incidence one way or another (in fact there was a tiny increased overall risk of about 3%, but it’s the sort of noisy result one can ignore). The results for the different types of cancer are mixed, with some showing increased or decreased risks, but no overall pattern or anything too dramatic. These results, in contrast to the myths of wholesome organic, have upset some people, especially the British Soil Association, the guardian of all things organic in the UK (including being the premier organic certification body in the country). 

Curcumin - Bioavailability Results

I have written before about curcumin, the yellow pigment from the spice turmeric, and its anti-cancer properties. In the lab there is ample evidence from petri dishes and test tubes, and evidence too from animal experiments aplenty. It seems to act in multiple ways across a wide range of different cancer cell types. On paper at least, it's one of the most promising of the food-derived agents and there are lots of people who are convinced that by itself it can act to protect from the toxicity of chemotherapy and radiotherapy, to act directly against the inflammation implicated in cancer-initiation and as a drug to kill established tumours. The reality is somewhat less impressive than all of the lab work suggests and the clinical trials to prove one way or another are mostly still in progress or not on the drawing board.

One trial that is in progress I have written about previously (www.anticancer.org.uk/2011/12/curcumin-trial-in-uk.html). It's a UK trial looking at curcumin combined with standard chemotherapy for inoperable colorectal cancer. The same team behind the trial have published some interesting results on one of the main issues in the use of curcumin as an anti-cancer drug: bioavailability. Like many other polyphenols with anti-cancer properties, such as resveratrol or quercetin, curcumin suffers fom low levels of bioavailabilty. This means that to get a therapeutic level a person has to take an awful lot of the stuff, and even then it's often doubtful how much gets through digestion and metabolism and into the tissues to do any good. In this trial patients took 5 × 470 mg (2.35 g total) tablets of Curcumin C3 complex for two weeks. This is a relatively low dose compared to some trials where patients took 6 g or even 12 g a day - that's a lot of tablets to take - and the question was whether this dose would even be detectable or not.

The first thing to report is that few patients (six of 24) reported side effects, and these were mild tummy upset, in contrast to studies with higher doses. In this trial only one patient out of 24 reported unpleasant side effects after two weeks of curcumin. The suggests that a good dose for future trials is between 2 and 3 g of curcumin a day. Blood tests revealed that curcumin was detectable in nine of 24 plasma samples, all 24 urine samples, and in the colonic mucosa of all 23 biopsied participants. High levels of topical curcumin persisted in the mucosa for up to 40 hours post-administration.

At the same time this trial asked patients about what they felt about taking curcumin as a treatment. Sixteen participants (67%) stated that they would take curcumin long-term should it be of proven benefit, providing further support for future trials.

While this is a long way from showing that there is a direct clinical benefit from taking curcumin, it's another small step in the right direction. The trial has established a dose that gives detectable levels of curcumin and its metabolites in the colon and has shown that there's some support from patients - with the important proviso that it's shown to be beneficial. And for that we still have to wait.

The results are published as open access here: http://cancerpreventionresearch.aacrjournals.org/content/6/2/119.long

Probiotics and Cancer Risk

The link between diet and cancer is complex enough for most people, but add in a genetic predisposition to cancer and the complexities go through the roof. While there are plenty of people out there with healthy diet plans and advice on what to eat to avoid cancer, when it comes to family histories full of cancer, doesn’t genetics trump diet? Is it really possible to reduce your cancer risk in spite of your family history? I am convinced that genes do not rule your destiny. Indeed one of the key things in my two compartment theory of Li Fraumeni Syndrome is that there are ways to massively reduce the risks of cancer even for people with mutated TP53 tumour suppressor genes. The same applies to women with BRCA1 or BRCA2 mutations – while there’s a definite elevated risk of cancer, it does not mean that there’s nothing that can be done to reduce the risks.

Which is why a recent paper published in the International Journal of Cancer makes for such interesting reading.  The title of the paper pretty much says it all:

Beneficial bacteria stimulate host immune cells to counteract dietary and genetic predisposition to mammary cancer in mice

Sadly this is not an open access paper that we can all read online. However, the authors of the paper had previously looked at the influence of probiotic bacteria on obesity, and that paper is accessible to all for those who are interested:

Microbial Reprogramming Inhibits Western Diet-Associated Obesity

In that work the authors fed mice a conventional ‘fast food’ diet and monitored the response – a set of obese mice. In contrast mice fed the ‘fast food’ diet but with added pro-biotic yoghurt avoided the onset of obesity, despite eating the same ‘fast food’ diet high in fat, sugar and low in vitamins and fibre. The addition of the yoghurt counteracted the pro-inflammatory effects of the poor diet.

In a detailed set of experiments the authors moved from looking at yoghurt to looking at the probiotic bacteria in the yoghurt, particularly a strain of bacteria called Lactobacillus reuteri. Mice fed the bacteria, in water and without the yoghurt, were still protected from the onset of obesity, and that the immune system was a key component of this positive effect.

In this latest paper the authors again use this beneficial probiotic but in this case they look at cancer development in mice. First they compared cancer development in mice fed the ‘fast food’ diet and those fed a more normal mouse diet. And, as you can probably guess, the ‘fast food’ diet was associated with both obesity and a higher incidence of breast cancer than the control diet. No surprise there. But the addition of probiotics to the diet reduced both cancer incidence and the size and growth rate of tumours that did develop. Now here’s where we get the surprise, because why should adding probiotic to the diet and helping the good bacteria in the gut, have an influence on breast cancer development?

The authors took this work a step further and then used mice with a genetic predisposition to breast cancer and fed one set the ‘good’ diet and the other set the ‘good’ diet with the probiotic. Now in these mice even the good diet led to cancer, though of course there was no obesity involved this time. However, and this is why this is such a great piece of news, the mice who also received the probiotic had lower cancer incidence, slower growing tumours and a longer survival time. In other words in spite of their genetic make-up there was a degree of protection from cancer just with the addition of a probiotic.

The papers go into much more detail on the mechanisms at work, principally to do with different classes of cells in the immune system, but that key result really stands out.

There are the usual caveats about extrapolating from mice to humans, but there is some evidence in people that yoghurt consumption can have a protective effect, both in obesity, metabolic syndrome and cancer. The next step is to take this work to another level and to start thinking about clinical trials. There are lots of ways we can test this out. For example, how about a trial in women with high risk of breast cancer recurrence? Or a trial in women with a genetic predisposition to cancer? And what about some work to see whether this protective effect can apply to other cancer types?

And, of course, there is nothing to stop people adding live pro-biotic yoghurt to their diets, or even taking pro-biotic tablets or drinks if they don’t like yoghurt.

Omega 3s and cancer - confusing results

I had been planning on writing a follow up to the last article on omega 3s and chemotherapy with a piece on new research that looked at a protective effect of omega 3s on breast cancer. However, the big news of the moment is the result of a study that found that an increased risk of prostate cancer from omega 3s. So what gives? For those wanting to know whether to increase or decrease omega 3 intake, these conflicting results are just down-right confusing and a bit scary too.

Let’s deal with the prostate cancer results first. The paper in question is called ‘Plasma Phospholipid Fatty Acids and Prostate Cancer Risk in the SELECT Trial’ and was published in the Journal of the National Cancer Institute (unfortunately not an open access publication). The abstract is available here: http://www.ncbi.nlm.nih.gov/pubmed/23843441. The authors looked at the relative percentages of different omega 3s fatty acids in blood samples from men with and without prostate cancer who had been enrolled in the Selenium and Vitamin E Cancer Prevention Trial. Men were ranked into four groups according to relative plasma omega 3 content and then the group with the lowest 25% were compared with the highest 25%. The results of this analysis showed that the men in the highest group had greater risk of prostate cancer than those in the lowest group. This was true for total omega 3 measurement as well as for individual omega 3s (e.g. DHA, DPA and EPA). On the face of it this looks like a pretty solid finding. But there are some puzzling things about this result. The first and the most obvious is that there’s no causal mechanism offered to explain a result that the authors themselves admit is puzzling and contrary to expectations. Omega 3s have many different effects in the body, for example they are strongly anti-inflammatory, but none of them known to be pro-carcinogenic or pro-tumour. Stranger still, the study found that some omega 6 fatty acids, which are known to be pro-inflammatory and often associated with being pro-cancerous, were associated with lower cancer incidence in this study.

Omega 3 Fish Oils and Chemotherapy

While chemotherapy remains the mainstay of treatment for most types of cancer, there will be a need to improve what’s called the ‘therapeutic index’. Simply put this is a measure of the good a drug does versus the bad. Chemotherapy causes all kinds of toxic side effects while killing cancer cells, and generally it could kill more if given at a higher dose, but to do so ends up causes a lot more damage. One way of improving chemo is through the use of new generation drugs that target tumour cells rather than the indiscriminate slaughter of the older drugs.

Another way to do this is to find ways of protecting normal cells in some way and/or making cancer cells more susceptible to the effect of the existing chemo drugs. Can this be done safely? According to some researchers the answer is a qualified yes. And the magic drugs that can spare normal cells but make cancer cells more susceptible to chemo are…omega 3 fish oils. There is mounting evidence that omega 3 fish oils, specifically eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), can indeed work in this way.

A new paper ‘Selective sensitization of tumours to chemotherapy by marine derived lipids: A review’, published in the journal Cancer Treatment Reviews (abstract here: http://www.ncbi.nlm.nih.gov/pubmed/22850619), goes over the evidence from cell cultures, animal experiments and clinical trials. And there is a lot of evidence to go over. The authors summarise it quite nicely, showing that the positive effect is there across many tumour types (including breast, prostate, colon, lung, lymphomas and more), and across chemo types (nearly all of the main classes of chemotherapy drug are listed).

One very encouraging aspect of this story is the number of active clinical trials looking at this now. The pre-clinical results and first analyses from those human trials that have taken place have all been positive. And when you factor in the other positive effects of EPA and DHA, such as helping to cope with stress (http://www.anticancer.org.uk/2012/02/omega-3s-stress-and-cancer.html), or a reduction in side effects (http://www.anticancer.org.uk/2012/08/peripheral-neuropathy-and-chemotherapy.html), then it really does begin to seem as though high dose omega 3s should be the one supplement that every cancer patient takes.

Milk, cancer and hype

The headlines were striking enough, for example the Daily Mail declared that 'Breast cancer patients who eat cheese, yogurts or ice cream could HALVE their chances of survival', while the Daily Mirror ran the headline 'High-fat dairy food increases risk of death in breast cancer patients'. The question is are these scary headlines warranted?

The source of the headlines is a study that looked at dairy intake in women after they had been diagnosed with early-stage invasive breast cancer between 1997 and 2000. These women were asked to fill in questionnaires about their diet, and these were followed up five or six years later. The researchers then looked at the associations with dairy intake and outcomes. The reported outcome was that intake of high-fat dairy was associated with a great risk of death, both from cancer and other causes.

The first thing to say is that this paper is not open access. It's published in the Journal of the National Cancer Institute (JNCI), which is a tax-payer funded body, and it's outrageous that scientific research like this is kept away from the public. When there's a story as potentially important as this then there's no excuse for keeping the data behind a pay-wall. US tax-payers should be demanding that the JNCI switch to open access publishing immediately.

That said, and without access to the full paper, there are some comments to make on what's reported in the abstract of the paper. Firstly this is a study that depends on questionnaires. This is one of the most unreliable sources of information on long term diet that there is. It depends on people being able to accurately remember what they eat and drink, and that they're not lying to themselves or trying to impress the people running the survey. In a long time frame, it also means the researchers have to make assumptions about the long periods between questionnaires. Remember, the researchers are trying to establish the cumulative intake of dairy.

The 2-Day Diet

It may seem odd to find a review of a diet book on a web site devoted to cancer, but there are good reasons for looking at this book. Firstly, it's an accepted fact that there is a strong link between obesity, metabolism and cancer. Secondly, there is an increasing view among some researchers that cancer is a metabolic syndrome, and that cancers are associated with a whole set of metabolic changes, both in the tumour and the surrounding tissues. Cancer and metabolism, and therefore diet, are inextricably linked. And, as discussed on this site in the past, there is evidence that altering diet can impact cancer treatments as in the work that looked at chemo response and fasting. There is another reason for looking at this book - the authors (Professor Tony Howell and Dr Michelle Harvie) are both working in breast cancer research, and are involved specifically in helping patients reduce their chances of getting the disease or reducing the risk of recurrence. One of the authors, Tony Howell, is well known to regular readers of this site for his work on the reverse Warburg effect and his association with Michael Lisanti and the development of new theories that link cancer with metabolism.

That said, this is primarily a book about diets and losing weight rather than a book specifically about cancer. Although the links to cancer are there in the text, and many of the patient stories include mention of cancer, the main aim is to help readers lose weight and keep it off. And, in doing so, to reap the overall health benefits across the board.

So, what is the 2-day Diet, and how does it differ from the thousands of other diet books on the market? A key point to make up front is that this is a diet that's been backed up by clinical data. There are no celebrity endorsements, no one selling expensive supplements or foods, no hand waving or bold claims unsupported by evidence. This is a diet that has been shown to work, it's that simple. Simple too is the basic idea behind the diet - it's simpler to stick to a strict diet for two days per week than it is for seven. And, importantly, the changes induced by a strict two day a week diet are significant enough to cause changes in body weight, glucose tolerance, mood and so on.

More On Stress and Cancer

A new open access research paper, 'Behavioural Stress Accelerates Prostate Cancer Development in Mice' (http://www.jci.org/articles/view/63324), adds more detail to the emerging picture of the relationship between stress and cancer. In this case the research team used mouse models to investigate the effect of stress on the development and progression of prostate cancer. And, as expected, those mice subjected to a stressful environment had greater incidence of cancer and higher rates of disease progression. And, just as importantly, some of the ill-effects of a stressful environment could be prevented through the use of drugs that interfere with the stress response to raised adrenalin and noradrenaline (i.e. like beta blockers).

From a science point of view this paper uncovers some of the molecular mechanisms at play here, which further advances our understanding of the relationship between psycho-social stresses, the resulting hormone stress response and the process of cancer initiation and progression.

However, it's the human angle that is of direct interest to me, (and to most readers of this article I would guess). What this new paper does is point out the horrible vicious circle that is at play here. As we know a cancer diagnosis is an incredibly frightening and stressful experience. It shakes your world up completely. The body responds to this stress by releasing adrenaline and other stress hormones. These can drive the cancer forward, causing even more stress as the disease progresses. It's not just the bad news. Cancer treatments are stressful too. Physically they are hard to take - there are side effects of drugs, radiotherapy and surgery. But there's also the stress induced by the whole process - the endless waiting, the delays, the uncertainty, the feeling of being disempowered.

Chemo, Radiotherapy and Fasting

A while back I wrote about some work by Valter Longo and his colleagues looking at the effects of short-term fasting on cancer progression (here: http://www.anticancer.org.uk/2012/02/fasting-and-chemotherapy.html). They showed that short term fasting can slow tumour progression in a range of different cancer types and can sensitise tumours to standard chemotherapy drugs. While this work was performed in mice, it was solid research that is already being followed up in a number of clinical trials.

In the latest update to their work, Dr Longo and his team report that short term fasting also helps to sensitise cells to radiotherapy. This time the work looked at gliomas - aggressive brain cancers - again in mice. This time they looked at how the standard treatments for gliomas, including glioblastoma multiforme, were improved by the adoption of short term fasting. Both chemotherapy (Temozolomide) and radiotherapy had improved responses in those mice subject to complete withdrawal of food for short periods (48 hours) compared to control groups.

These results are in mice, but again there is no reason why they should not apply to people. Though whether there is the same degree of response is an open question which can only be answered through clinical trials.

For the moment this is yet another small step forward and confirms once again that cancer is more than a disease of delinquent cells, and that disordered metabolism is a key feature with clinical significance.

For those wanting the full details of this new research, it has been published in the open access journal PLOS One: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0044603

The final word has to be this. If you're a cancer patient and want to try this out for yourself, make sure you talk to your oncology team to ensure you get the support you need.

Peripheral Neuropathy and Chemotherapy

Side effects from chemotherapy can often be worse than the symptoms of cancer itself - as many patients know, and as we know from our experiences with our son George. For taxane-based chemotherapy, such as Taxol, Paclitaxel and Docetaxel (which is one of the drugs that George had), one of the worst side effects is called peripheral neuropathy. This involves nerve damage, particularly in the hands and feet. It usually manifests as tingling, numbness, burning or pain, but can also involve blood pressure changes, balance problems, constipation and a range of other problems.

It can be severe, and in our case it got so bad that George ended up having to come off treatment, with disastrous results in the end. Again, this is common, and so-called 'dose limiting toxicities' mean the treatments are scaled back or stopped, even when they are showing some signs of effectiveness. Obviously, finding good ways to stop the side-effects means that patients can continue with treatments, and also their quality of life doesn't descend into misery.

Which makes the results of a recent clinical trial worth noting. This was a randomised placebo-controlled trial - which means some patients got the treatment and some got a dummy pill and then the two groups of patients were compared to see what difference the treatment made. The trial was specifically looking at peripheral neuropathy in cancer patients being treated with Paclitaxel. And the treatment being tested? Omega-3 fish oil capsules three times a day. Yep, good old fashioned fish oils rather than some fancy new drug.

The results? 70% of the fish oil patients didn't get peripheral neuropathy, will in the control group it was only 40% that didn't. Not only that, there was a clear tendency for the symptoms to be less severe in the fish oil group for those patients who did suffer some symptoms.

Given all of the other positive benefits of fish oils, this is certainly a study worth bringing to the attention of your oncologists if you're being treated with Paclitaxel or other taxane-based drug. Let's hope that the trial is replicated soon so that results are confirmed.

Anyone looking for the details should take a look at the (open access) paper reporting the result here: http://www.biomedcentral.com/content/pdf/1471-2407-12-355.pdf

BBC Catches Up With Anticancer.org.uk

I know that's a bit of a cheeky title, but I do feel the need to point out that today's story on the BBC website: 

Curry's ability to fight cancer put to the test

is about the curcumin and chemotherapy trial that I wrote about here on the 19th December 2011:

http://www.anticancer.org.uk/2011/12/curcumin-trial-in-uk.html

In any case, it's a story worth keeping an eye. Of the many naturally derived substances that show anti-cancer ability, curcumin is one of the most promising, but also one of the most problematic. As a single agent it clearly doesn't have a strong enough anti-cancer action, even at high doses, so combining with other agents, like standard chemotherapy drugs, is a good strategy.

Ultimately though, I strongly suspect that it will be engineered molecules that are derived from curcumin that will make it into the clinic first. There are already different curcumin analogs showing promise in animal models - though none have made it to patient trials so far.

Fasting and Chemotherapy

In a recent article on Low Carb Diets And Cancer, we looked at some interesting results of studies on low carb diets on established tumours. The conclusion to that study showed that a low carbohydrate, high protein diet:

...reduces blood glucose, insulin, and glycolysis, slows tumor growth, reduces tumor incidence, and works additively with existing therapies without weight loss or kidney failure. Such a diet, therefore, has the potential of being both a novel cancer prophylactic and treatment, warranting further investigation of its applicability in the clinic, especially in combination with existing therapies.

Well, you can’t get lower carb than not eating altogether, and that’s exactly what another new paper explores as an option. Published in the journal Science Translational Medicine, you get a clear idea of what it’s about from the title: Fasting Cycles Retard Growth of Tumors and Sensitize a Range of Cancer Cell
Types to Chemotherapy. As with the previous paper, much of the data in this paper comes from mice models of cancer. So, as always it’s important to keep in mind that what works in mice doesn’t necessarily work in humans. Aside from anything else, mice don’t have to cope with the stress of knowing they have cancer…

Omega 3s, Stress and Cancer

Stress is a fact of life for cancer sufferers not just when they are undergoing treatment, but beyond that too, once they are in remission. It’s a fact life for people with Li Fraumeni Syndrome and other TP53-related conditions, and for those with Lynch Syndrome or other inherited conditions that predispose to cancer. This would be bad enough if we didn’t also know that stress can negatively affect the health, including negatively affecting the immune system. And, to cap it all, this knowledge itself causes stress, thereby creating one of those horrible vicious cycles that can lead to depression and anxiety.

Before reaching for the anti-depressants though, there are some positive things that can be done to tackle this stress. And, as a bonus, many of these steps to tackle stress can also boost the immune system and generally have a positive effect on health. What’s more, there is also accumulating evidence that many of the steps that I will outline are also good for people in the middle of cancer treatment, not just those who are in remission or worried about the next test results.

These positive steps include:

• Exercise
• Meditation
• Tackling sleep problems
• Improving diet
• Omega 3 fatty acids

Cancer and lifestyle choices

The headlines are startling: over 40% of cancers are down to lifestyle. The opening paragraph of the BBC News report states it bluntly:

Nearly half of cancers diagnosed in the UK each year - over 130,000 in total - are caused by avoidable life choices including smoking, drinking and eating the wrong things, a review reveals.

For those with cancer, or who have family or friends suffering from the disease, this makes for grim reading. Because, like it or not, there's a moralistic sub-text here: in over 40% of cases, cancer is the fault of the patient. If only they'd chosen the right life-style, they wouldn't be sick.

Now, that isn't what the articles say, but it's a clear implication. Before we go any further though, perhaps we ought to back up a little and ask what the science really says...

Firstly, we have to be clear that what we're talking about here are projections based on a series of mathematical models. These projections take a series of risk factors - say smoking or alcohol consumption - and then compare the increased risks of developing cancer based on comparing current consumption levels and what are considered the 'optimum' levels. So, for example, you take the additional risk of developing cancer per unit of alcohol, the difference between current consumption and the ideal level and calculate the increased risk. Now take that increased risk and multiply by population and you get your projected number of cancer patients. It's a bit more complicated than that, of course, but in principle that's how it works. Add an additional set of factors for different types of cancer, and you've got a cascade of different variables that make up that final scary number.

So, all of this is subject to many different assumptions about risk factors, current consumption levels, ideal consumption levels, population growth etc.

Dealing With Stress

Coping with cancer is obviously stressful. Not just for the patient, but for friends and family too. And it’s not just during treatment, the stress can be there even after a patient is declared to be in remission. A new paper, from Duke University Medical Center in the US, reports that post-traumatic stress is prevalent in cancer patients even in long-term remission.

An added factor in this stress is the well known fact that it can have negative effects on the immune system, cause depression and generally make things worse. There is also the worry that stress can make the disease worse, or can make it recur in patients in remission.

So, for all of these very obvious reasons, it’s important to look at what can be done to tackle this issue that can severely impact the quality of life for all of us. The good news is that there are some active steps that can be taken and which don’t involve taking more drugs.

Diet is one factor that may play a part in the ability to handle stress and deal with depression. There is plenty of evidence to show that diets having higher levels of omega 3 fatty acids helps the body deal with stress – it has been shown to reduce the levels of stress hormones and can improve mood and the ability to cope. In fact higher levels of omega 3 – obtained from supplements rather than diet – have also been used to treat depression. And, as a bonus, higher omega 3 than omega 6, helps reduce the inflammatory factors that are shown to be associated with cancer. As a bonus there is emerging evidence that omega 3s are helpful in coping with cancer treatments, and are being investigated for use against cancer cachexia in advanced disease.

Q&A with Dr Gerald Krystal - Low carbs and cancer

Following my recent article on a recent paper that looked at the effect that a low carb diet had on slowing tumour growth (and if you haven’t read it, I suggest you do that before reading the rest of this…), I contacted one of the authors, Dr Gerald Krystal of the University of British Columbia with a list of questions. Dr Krystal has kindly responded with some more information, which I think is useful for those people considering starting a low carb diet in line with the results of his team’s work.

PP: The low carb diet includes foods high in amylose. Doesn't this make it difficult to translate into a diet people can follow? Are there foods that are naturally high in amylose?

GK: There are many foods that are naturally high in amylose. For example, all legumes (beans, lentils and peas), basmati rice, new potatoes, bananas, whole grains, sweet potatoes, radishes and parsnips. Try and avoid regular "old" potatoes, white rice and white bread (whole wheat bread is not much better….bread with whole grains is the best when it comes to breads but I try and avoid all breads. If you can't resist, sourdough is not bad because of its low pH…if you add a tsp of lemon juice or vinegar to any meal you can lower the glycemic index by about 1/3). Another interesting tip is if you let cooked rice cool it becomes more resistant to digestion so eating sushi is better than eating hot cooked white rice. I would love to see a breakdown of digestible carbs into % amylose and % amylopectin down the road on food products. Also, there are ongoing studies in the US to generate genetically modified potatoes (lacking 2 enzymes that are used to put the branched sugars on the glucose polymer to convert it from a linear glucose polymer (amylose) to a branched glucose polymer (amylopectin, which is more easily broken down). Don't know how you feel about genetically modified foods but this could dramatically lower blood glucose spikes after eating potatoes.

PP: Why is it that so much mainstream dietary advice for cancer patients seems so unhealthy? Why are patients still being encouraged to have high calorie diets?

GK: This drives me crazy as well. The main concern of cancer clinicians today is cachexia (wasting). I understand this is something you want to avoid but I think that lowering our carb and raising our protein intake will have a substantial benefit, especially for early pre-metastatic cancers. In keeping with this I would like to see clinicians substitute amino acid/PBS intravenous drips for the currently used 5% dextrose (glucose) PBS to rehydrate cancer patients.

Low carb diets and cancer

The Warburg Effect

It is well known that a hall-mark of cancer cells is an increase in the use of glucose – the so-called glycolytic switch is an early indicator of malignancy (a change that is a part of the Warburg effect – which is worth following up if you're interested). This greediness for glucose is exploited in PET scanning, where radioactively tagged glucose is injected into the patient and, several hours later, a scan is taken to track where the radioactivity has accumulated in the body. Tumours absorb much higher amounts of this radioactive glucose than the normal tissues, and show up as 'hot spot' on the scans.

Tackling this greediness for glucose underlies a number of different approaches to attacking cancer, and one obvious avenue for this is to look at diet. Before we get into this, however, it's worth pointing out that many mainstream oncologists and dieticians are incredibly blasé about this topic. From our experiences in many different hospitals and with different doctors, we know that the mainstream advice for cancer patients is not to change the diet in any major way. Time and again we were told that keeping the calorie intake high and maintaining weight were the most important considerations. Any questions about limiting carbohydrate intake to starve tumours were simply dismissed as untested and unproven hypotheses and therefore best avoided.

That said, there have been numerous studies that have looked at the influence of diet on cancer growth. Many of these have been rodent studies, but there have also been some patient studies performed, mostly these have looked at brain tumours (glioblastoma). Furthermore, much of this research has involved a ketogenic diet, which is a high-fat and extremely low-carb diet, which has been used clinically in the treatment of epilepsy. In terms of being able to follow this yourself, it's no easy task, this is an extreme diet, much more extreme than the strictest Atkins diet for example.

Miracle Cures

Beware Of False Prophets

It is tempting for cancer sufferers, and their friends and family, to look around at other treatment options, particularly if current treatments start to fail. In some cases people want to complement what they are getting from their oncology team – either because they want to lessen some of the horrendous side-effects of chemo or radiotherapy or because they want to boost the effectiveness of the protocol they are on. There are some people who simply don't want to go the conventional route – though this is a very high-risk strategy to adopt and is not one that is recommended (this is a topic that I will come back to in a future post). In other cases conventional treatments fail, the disease progresses or recurs, and there are few standard options available so the search for something new takes on a particular urgency. The first port of call for people in these different situations is the internet. And this too, can be dangerous, as you soon discover.

The last time I looked, the search term 'cancer cure' came up with 103,000,000 hits. Yep, 103 million hits. That is an unimaginably huge cache of information to process. And, unfortunately, a lot of that information is both dangerous and worthless. In our search for treatment options, (particularly once George's treatments started to fail), we came across plenty of sites that were offering miracle cures for cancer. No matter what type of disease, or at what stage, there were people out there who were promising to both treat and to cure. That alone should be setting alarm bells ringing in any sane person.

In general there are two distinct subsets of these promised cures, with some more credible looking than others.  On the one hand there are the promised cures that appear to be based on science and those that are decidedly, and in some cases proudly, unscientific.

Book Review - Foods To Fight Cancer

A version of this review was first published at LondonBookReview.com

Title: Foods to Fight Cancer
Author: Richard Beliveau and Denis Gingras
Publisher: Dorling Kindersley
ISBN: 1405319151/0756628679

Cancer patients, and their friends and families, are often faced with contradictory information on what to do about diet. On the one hand there are large numbers of mainstream oncologists and dieticians who tell patients to eat what they like so long as they keep the calories up and are able to get through chemotherapy or radiotherapy. On the other hand there are plenty of people who insist that only a strict vegan or macrobiotic or Gerson or other anti-cancer diet will help. And of course there are lots of books out there that advocate all kinds of diets, all of them claiming to be based on some sort of science. Those looking for a middle ground based on solid science are left trying to work out for themselves what makes sense and what is obvious nonsense.

Foods To Fight Cancer looks like lots of other books in the 'superfoods' genre. It's glossy, well illustrated and published by Dorling Kindersly. It looks more coffee table than operating table. However, unlike many of the anti-cancer food books that are on the market this one is written by scientists working in the field of diet and cancer and who are not only up-to-date with the science but who are engaged in making it happen. It just so happens that Richard Beliveau and Denis Gingras are excellent communicators able to write for the non-scientist as well as their colleagues.

The central premise of the book is that dietary interventions can help tip the odds against developing cancer, and also to aid in fighting cancer once it has started. The plant kingdom contains thousands of phytochemicals - polyphenols, terpenes, sulphides etc - which have potent anti-cancer properties. These micro-nutrients act in multi-faceted ways to block many of the different biological pathways necessary for cancers to form, grow and then metastasize. Unlike some of the over-inflated claims made by some, there is no promise of a single all-powerful cancer cure here. Instead the emphasis is firmly on looking at what pathways are necessary for cancer to develop and then what can be done to block these using multiple compounds from different foods.