June 19, 2018

A Closer Look at the AICR’s New Expert Report on Cancer Prevention

Interview with American Institute for Cancer Research (AICR) Director of Research Nigel Brockton, PhD

In this interview Nigel Brockton, PhD, describes the most recent expert report produced by the American Institute for Cancer Research (AICR). The AICR is a highly-respected non-profit organization leading the charge against cancer globally. This latest report provides a blueprint that practitioners and patients can use to help reduce cancer risk.

For more information about the AICR, visit aicr.org. You can also find a lifestyle evaluation tool at cancerhealthcheck.org.

Approximate listening time: 24 minutes

About the Expert

Nigel Brockton, PhD, is the director of research for the American Institute for Cancer Research. A two-time cancer survivor, he likes to bike to work every day.

He is a keen skier, cyclist, and cancer research advocate leading the research at AICR to focus on the links between diet, weight, physical activity, and cancer throughout the cancer continuum—prevention, treatment, and survivorship. He combines all of his passions to encourage active lifestyle in the community and support people affected by cancer.

Brockton has been interested in cancer prevention since he was diagnosed with Ewing’s Sarcoma at age 18 (1989) and again at age 21 (1992).

He has a PhD in genetic epidemiology of colorectal cancer risk (Aberdeen, Scotland). Before coming to AICR, he spent 10 years as a Cancer Researcher in Alberta, Canada.


Karolyn Gazella: Hello. I'm Gazella, the publisher of the Natural Medicine Journal. As a cancer survivor, I must say, that I am thrilled to be talking about a topic that is near and dear to my heart and that is reducing the risk of developing cancer. And I'm equally thrilled to have with me Dr. Brockton, who is the director of research with the American Institute for Cancer Research.

Dr. Brockton, thank you for joining me.

Nigel Brockton, PhD: Thank you for having me.

Gazella: Well, you know, before we dig into this latest report, which is the subject of today's interview, please describe the mission of the AICR.

Brockton: So, the American Institute for Cancer Research focuses on the links between diet, weight, physical activity, and cancer risk throughout the cancer continuum from prevention, treatment, and survivorship. The modifiable lifestyle factors that we all know can change your risk of cancer and, ideally, improve your outcomes after a cancer diagnosis.

Gazella: Perfect. Now, you mention that we all know this, but I have to say that there was a time, and not that long ago, where some healthcare professionals actually felt that it was not possible to prevent cancer. Now, based on the research from AICR and other organizations, how confident are we that we can, in fact, reduce the risk of developing cancer?

Brockton: Absolutely confident. It's important to remember that there are no guarantees. We can't declare that if you do these things, you will not get cancer, but we absolutely know that if you do these things, you do reduce your risk of cancer. It's estimated that approximately 40% of cancers are preventable by health-related choices and those include being physically active, achieving and maintaining a healthy weight and eating a healthful diet.

Gazella: Perfect. And that's a large percentage, so that's great. Now, let's dig into this latest report. Tell us a little bit about the process that was used to create the report released by the AICR.

Brockton: Little bit of history, the first report was actually produced in 1997, the second one in 2007. And after the 2007 report, the growth in the literature has been so great, even before the 2007 report, but it's continued to grow ... The AICR and WCRF Network International thought we really need a process that is more nimble to try and do this, 'cause it's such an enormous task to undertake and to do this review. And we're the only entity doing it on this scale and looking at the whole picture, rather than just individual disease sites or individual exposures.

Back in 2007, the Continuous Update Project was born and this really took the lessons that were learned from the first and second expert report and, sort of, consolidated it into a process to make it a very transparent and robust process.

There's a centralized database, getting on toward 10,000 studies summarized in that database, with all of the exposures and the study designs and all the parameters of the study. Each disease site is taken on a, sort of, rolling stock, if you like, so in 2017, we updated the breast and colorectal reports that had been done in 2010.

This is a more nimble process than just every 10 years trying to do a single, massive report. But it is, ... Each site has a, it's like a funnel of evidence from the, looking at the exhaustive systematic literature reviews. To give you an idea, the systematic literature review on which the breast cancer continuous update project report is based is over 2,200 pages. The breast cancer continuous update report itself is 120 pages, so that's a distilled down, what's the most important, essential information?.

And then, for our third expert report, which is all of these cut reports, plus the supporting chapters of the cancer process, judging the evidence, cancer survivors and all the exposure chapters constitutes about 2,000 pages in total of content. But it's all following this very sort of strict and transparent process of summarize the evidence, create the cut reports.

The cut report stage the panel get together and assess how strong the evidence is and then make recommendations based on that. There's an international panel of 12 members who are the most senior and knowledge people in the field and they are the ones that look at the evidence that has already been assessed through various rigorous statistical techniques to then make their final human recommendation.

Gazella: Yes and I have to say I've been following the work of the AICR now for years and you mentioned rigorous and that's one of the reasons I was so drawn to the organization in the beginning because you do apply such rigor. And this is a massive project and a massive undertaking.

The information gleaned from this is just so important, and I'm just wondering what's the most surprising or compelling fact that was revealed in the at least report, if there even was something that was surprising or compelling?

Brockton: I think the most compelling aspect is the consistency of the findings. Fundamentally diet physical activity and body weight remain the key elements of our lifestyle that we can control and that have a big impact on cancer risk. And the whole field of lifestyle research has evolved over the three decades since AICR first attempted to summarize the global literature.

And that evolution has really been in response to some of the criticisms of the earlier research and the ecological type studies the case control type studies and the evidence now so much of this last report is based exclusively on prospective cohort and randomized control studies. The evidence is stronger and higher quality than it's ever been. But we're still really finding the same fundamental answers that it's body weight, diet and physical activity and the fact that, that's good stable reliable and effective advice is good news for people who want to know what changes to make in their lifestyle.

Gazella: Yeah absolutely and it certainly directs health care professionals in terms of what they need to be telling their patients. And I'm curious now you've mentioned diet weight and physical activity, are we looking at these equally or does one of the three bubble to the top as being something really, really important to emphasize?

Brockton: We certainly intend them too be used as a package. We don't want people to cherry pick. well I'll do this one and ignore that one. But saying that I think Karen Collins, one of our people, said it best and she said, "This is a call for action not perfection." Any changes people can make towards meeting these recommendations is good, but ideally we should be addressing all of them.

That being said there's effectively one recommendation for physical activity, and one recommendation for body weight because those are fairly well defined. Be active, be a healthy body weight. Whereas it's more difficult just to say to someone eat a healthy diet because there are some, let's say, differing ideas about what is healthy. That's why we've tried to pick out particular aspects of the diet that tend to be attributes of either particularly healthy diets or particularly unhealthy diets to give people advice that they can really use and implement in their daily lives.

Gazella: Yeah let's talk a little bit about that more. At the Natural Medicine Journal we've actually looked at the research associated with the Mediterranean diet. Not exclusive to oncology we obviously are looking at cardiology and other aspects as well.

How would you describe the diet that the AICR likes to endorse? What's your description of that diet?

Brockton: I wouldn't strictly call it the Mediterranean diet. I think the Mediterranean diet is defined in many different ways and in the terms that it's actually presented in the literature is often a Mediterranean lifestyle not specifically a Mediterranean diet. It doesn't just include it because people often say, "Well they eat lots of red meat and red wine."

We don't endorse any particular named diet. We have our own program if you like the New American Plate but it's two thirds of your plate should be plant-based foods. We recommend certainly for cancer prevention not drinking alcohol, but at least limiting it to national guidelines. We don't tell people that they should absolutely avoid red meat but we say they should eat modest amounts—that's 12 to 18 grams a week. And we emphasize plant-based foods and real food, avoiding processed food and fast foods.

We don't have a jazzy name for it but it's a pretty pragmatic collection of recommendations.

Gazella: Yeah, absolutely.

Now I'd like to switch gears a tiny bit 'cause you know some of our practitioners have difficulty getting their patients to actually change their behaviors when it comes to cancer prevention. It seems like patients aren't really thinking of cancer until they're diagnosed, which is really truly unfortunate. What steps does the AICR take to help motivate people to create more lasting change when it comes to a healthier lifestyle?

Brockton: I think the first step is always awareness. Every couple of years we do a cancer risk awareness survey, and it's always astonishing because we are immersed in this topic all the time. It's astonishing to us that over half of the people in the US don't realize that body weight is related to cancer risk. That they don't realize that physical activity is related to cancer risk. These are components that people readily associated with cardiovascular disease but they're not aware that they have a impact on cancer.

As I mentioned we do have our New American Plate with the 12-week program with the interactive supportive Facebook group where people can discuss the challenges of following the program or just looking for recipe ideas. We have educational materials, infographics, brochures. But I do think awareness is probably our biggest problem at the moment. As you say, people don't think about it until they're diagnosed and then suddenly they're interested in what could be done.

One of the priorities for the AICR is to look for exposures over the life course. Because it's important that people actually adopt these recommendations early in life for the greatest impact on reducing their risk. We'd like to make that awareness as early in life as possible as well.

Gazella: Yeah that makes a lot of sense. Cancer has become so prevalent, unfortunately, is it the AICR's view that all individuals should be looking at lifestyle factors to reduce risk or only those patients who are at a higher risk to begin with?

Brockton: Our recommendations apply to everyone. They're not specifically restricted to people at higher risk. It may be that people who realize that they're at a higher risk may be more motivated but theses are not, they don't specifically apply to the higher risk people and in fact most of the research that's been done has been done on general populations rather than higher risk ones. We don't specifically know that these recommendations will actually have a greater effect on people that are higher risk because those tend to be smaller more targeted studies.

Gazella: Yeah that makes a lot of sense and I think that in the work that I've done and the work we've do with the Natural Medicine Journal we would agree that this is a conversation that healthcare professionals should be having with all of their patients just because of the fact that 1 in 2 men and 1 in 3 women, it's predicted, will develop cancer in their lifetime. This has become epidemic in proportion almost.

Brockton: Yeah everyone knows somebody who's been affected by cancer. We all have an opportunity—particularly health professionals—but all of us have an opportunity to try an encourage our friends colleague family to make some of these changes, all of these changes ideally.

Gazella: Yeah absolutely but I do what your colleague said, "Call to action not perfection." Because I think sometimes patients get intimated by, "Oh my god, I have to change this and this and this and this." And sometimes small steps are the way to go, so I do like that quote.

I'm actually going to use that I think in the future.

Brockton: Absolutely and I think that when people succeed in meeting one goal it makes them more keen and more motivated to then start chipping away at the others and it can, if you look at them as a ... Although we present them as a package, if people look at them too much as a package and think I have to do all of these then they may feel daunted or intimated and not succeed.

We do definitely want to get across, "Do what you can, but also aim high."

Gazella: Right, that's true. Don't give up, don't give up.

Now let's talk about the future. As the director of research of the AICR what projects or research initiates will your organization be focusing on in the coming months and even the coming years?

Brockton: As director of research the biggest thing for me is funding innovative and impactful research. Every year we fund a number of grants which really try and, again, chip away at our understanding of cancer and how to reduce the risk and improve outcomes. That's an ongoing process.

The Continuous Update Project will continue and we hope to improve it and expand it to other kinds of sights. The ones that we focused on so far are the ones that lifestyle factors seem to have the biggest impact, but there is increasingly evidence that some of the cancers that haven't really been associated with lifestyle factors are still affected by them. And also looking the new ways to raise money so we can do more of the stuff that we do.

Gazella: Yeah that's right. Yeah it's amazing how all of that requires all of that support that you're providing to people requires money doesn't it?

Brockton: It does. I find it very easy to try and encourage people to raise funds for it because I know how important this work is and how good the work we do is. But you still gotta get them to commit.

Although, we know so much more than we used to there is still so much that we don't know and I think the best example for that is really in the survivorship realm, where in 2014 we did the breast cancer survivor Continuous Update Project Report. Intuitively, we believe that all of these factors do improve outcomes after diagnosis of cancer, but if you take the very rigorous approach that we've taken to assessing the literature it's very hard to ... Basically none of the factors on its own reaches the level of strong evidence that's convincing or probable. In order to be able to make specific recommendations to cancer survivors we need that evidence to rely on, and it's coming but it's just it's not there yet.

The best example is that if we want people to change their behaviors at diagnosis we need to have evidence that shows that changing those behaviors changes those outcomes. We know that for instance if people are physically active at diagnosis they tend to have better outcomes but what we don't know is if they become physically active after diagnosis does it change their outcome. And this also is relevant for body weight, if they're have over weight or obesity at diagnosis and then they achieve a normal body weight does that improve their outcome.

And there's some reverse causality kind of weight projection issues that play. There's still so much we need to do.

Gazella: Yeah absolutely but I love the fact that you have this focus on survivorship because I think now especially with the commission on cancer survivorship mandate I think everybody, cancer centers and doctors, I think they're all looking at this population differently and they have special needs. And they're worried, they're fearful of getting their cancer back and if we can help them on any level, and I think lifestyle diet and lifestyle is a perfect way to help them, I think that that's brilliant. I'm so glad that you have a focus on that in the future I think that's really great.

Brockton: Yeah I think it has many benefits, as a cancer survivor myself, it's the empowerment that you feel that there's something you can do and it's not just up to the doctors. And the fact that it may improve your outcomes as well. It gives you power over your own destiny and especially after the, I didn't feel it myself, but I know people who come out of the end of chemo-therapy or radio-therapy and then they feel they're just sort of cast into the community to wait and that's a very tough thing to deal with. The fact that you can then say, "I'm going to invest my energies in having the best chance possible." I think that's a very empowering thing to be able to do.

Gazella: Absolutely, I would agree. And I want to remind our listeners we're going to have a link to the AICR website so please check it out and that is AICR.org and we will have a link underneath this audio interview.

One again, Dr. Brockton thank you so much for joining me today and congratulations on this wonderful report. What a great gift that your organization is giving to the world.

Brockton: Thank you and you might also want to just check out cancerhealthcheck.org. It's a very quick 11 question survey to help people look at their lifestyle and work out, which areas they could maybe improve. And full disclosure I could definitely improve with eating fewer cookies.

Gazella: Well I'm not even going to talk about red wine then. Let's just leave that all alone. That is a great reminder though. I did see that you recently launched that and it's cancerhealthcheck.org. We will put a link to that one as well because that too is really a great tool that our listeners can refer their patients to. That's a great tool so thank you for that reminder.

Thank you again for joining me and have a great day.

Brockton: Thank you very much bye, bye.

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