Transdisciplinary Energetics and Cancer (TREC)


Obesity and cancer?
Why are we meeting in Philadelphia?
These are question not commonly asked on our CNiC blog. Let me explain a little of our new center on obesity and cancer, and link you to our related resources.

NCI convened the first meeting of funded centers working together on issues relating energy balance, obesity, and cancer. My role at this meeting with Sarah Gehlert, leading our TREC at Washington University in St. Louis was to provide an overview of our Center and the projects we have embarked upon to address obesity and cancer, with a particular focus on translating our findings to the burden of cancer in Missouri. See our web site. 

Our 5-year funding sets us in motion to bring faculty together across our university and with neighbors across our state to move forward counteracting the burden of cancer due to obesity. We have previously written on just how great this is for our nation.(see Obesity and Cancer. Wolin, et al. 2010.) Now we are linked to colleagues in other centers to learn from our collective efforts. 



The quick summary of our center is available through this link. "Transdisciplinary Center Approach to Examine Multilevel and Multigenerational Associations Between Obesity and Cancer". 


Over the coming months we will add updates on progress as we expand our research and translation to practice to address obesity and prevent cancer.

(Video) Eight Ways to Prevent Cancer - Exercise

Next up in the Eight Ways to Prevent Cancer video series: Exercise.

CNiC's Dr. Kate Wolin walks us through the huge benefits we get from exercise, including a lower risk of heart disease and diabetes, on top of the cancer benefits many people may not be aware of. The video also highlights the fantastic progress of a cancer survivor who went from walking just over a 1,000 steps per week, to over 6,000 steps per day - on her way to an ultimate goal of 10,000 per day.

Wolin's quote sums it up best:  "It's never too early to start being active, but it's certainly never too late."

Timing is everything: Renewing the debate on aspirin

This week on the NY Times Well Blog is a discussion of whether the health benefits of aspirin have been oversold (or the health risks underreported). The spark to this renewed discussion is a Cochrane review of the aspirin data. What gets lost in the debate, is how important timing is when considering the health benefits of aspirin use. As we've previously noted here on CNiC, the benefits of aspirin use for colorectal cancer risk reduction and reduction in colorectal cancer mortality really become apparent after a decade or more of use. With a mean follow-up of 6 years, the latest review by Seshasai et al, wouldn't capture the full benefit of regular aspirin use.

Meat: Not for Dinner Tonight

This week was full of news about meat. The week started with news from the Department of Agriculture that US red meat consumption is expected to be lower in 2012 than it was in 2007. Of course, global meat consumption isn't down, which means the US is continuing the trend we started with tobacco of exporting our bad habits abroad. As Mark Bittman noted in his New York Times OpEd, Americans are choosing to eat less meat, not just because of price changes, but because of the negative health and environmental effects of eating red meat.

Which is good news, since the week is ending with more research on the carcinogenic effects of red meat consumption. We've talked a lot on CNiC about how red meat consumption increases risk of colon cancer. This week, a meta-analysis (i.e., a study of studies) in the British Journal of Cancer reports consumption of red and processed meats significantly increase pancreatic cancer risk. They found a 30% increase in pancreatic cancer risk with red meat consumption in men.

This is exactly the kind of science that is the foundation of the 8 ways to prevent cancer. If you want to learn more about your personal risk for pancreatic cancer, head over to Your Disease Risk.

(Video) 8 Ways to Prevent Cancer (and A Bunch of Other Diseases)

As part of our 8 Ways to Prevent Cancer campaign, the Siteman Cancer Center and the Cancer News in Context team produced a series of videos focusing on practical information and useful tips about each "way."

This is the first in the series, featuring CNiC's Dr. Kate Wolin.

Simple tips.  Big benefits.

Confronting the challenges of 2012 with salads and stairs

In Sunday's New York Times, the editors ask prominent economists to weigh in on how to face the economic challenges ahead of us in 2012.  Richard Thaler, of the University of Chicago, who wrote (with Cass Sunstein) Nudge, the best selling book on behavioral economics argues that employers have the opportunity to tackle one of our biggest challenges, health care spending.  Employers are choice architects - they can make changes in how choices are offered that make one choice easier, or the default.  Thaler argues that by making a few changes, employers can improve workers' health, leading to greater productivity, fewer sick days, and lower insurance costs.


First, Thaler argues, make eating at work easier, by prominently featuring a variety of healthy options and putting in an attractive salad bar before the burger line.  How might this look in real life? Let me use the cafeteria at my office as an example.  

There are at least four cafeterias on our hospital/medical school campus and they aren't all run by the same people, so the situation likely looks different on the other side of campus, but this is what it looks like in the cafeteria that sits right under my office and nearest the cancer center.  The first thing you see when you walk in, is the grill/fry-o-later area.  Serving up burgers, hot dogs, fries and onion rings, it invariably has a long line, which makes it easy to miss that there is a sandwich counter immediately to your left.  The sandwich counter is hidden behind a high wall and camouflaged further by shelves of chips and candy, so unlike in many sandwich shops, you can't see the choices.  You can see two featured sandwiches.  Sometimes one is healthy, but not always.  Just past the sandwiches (and around the candy display) is the hot meal counter, which features one Weight Watchers entree each day.  This may reflect my own food preferences, but I rarely find this entree to look very appetizing or particularly healthy (I realize “healthy” can have lots of different meanings, but something high in cheese and refined grains rarely meets my metric).  To the far right of the sandwich bar is the pizza station, which usually features 3-5 types of pizza (most laden with meat) and another cheesy doughy option, like calzone, daily. Across from the sandwich bar is the featured entree special of the day.  The days I've visited in recent memory this has been: nachos loaded with ground beef and processed cheese of the orange variety ( which I confess to finding appealing on Super Bowl Sunday, but I'm not kidding myself about it fitting in the healthy realm and I accept the health consequences of my choice), and beef stir fry laden with sauce of the kind women's magazines regularly tell readers to avoid choosing when dining out, roast beef covered with gravy and accompanied by mashed potatoes. Just past the featured entree is the salad bar. I think most cafeterias these days have a salad bar, but having a salad bar and having an “attractive” salad bar are not the same thing. To their credit, since I started at my office nearly 5 years ago, the cafeteria has added mixed greens and baby spinach as daily options, offering something other than the white-ish iceberg lettuce of the early days. And there are proteins in the salad bar choices - typically hardboiled eggs, one type of canned bean and diced turkey or tuna. But the salad bar is a long way from what I’ve seen else where and a long way from allowing you to create the kind of salad you might get down the street at one of the neighborhood sandwich shops. Dried fruit? Nope. Other kinds of fruit? It is on the other side and is charged at a different rate. Nuts? No, but there are sunflower seeds. Cheese? Yes, there is usually grated orange cheese. I give the cafeteria credit, I can definitely create a greek salad for myself that rivals that fancy sandwich shop on the corner (with the possible exception of the tomatoes that always look a bit iffy) at a fraction of the cost. But it doesn’t look “attractive” and I’ve got to do all the work, which perhaps explains why there is never a line at the salad bar and I am 10 times more likely to see the people in front of and behind me at the checkout with fried chicken than a salad. This, I think, gets to the fundamental point - if you want people to make the healthy choice you have to make it easy and attractive.

What about Thaler’s other suggestions? His second is making exercise easier. The health benefits of exercise, as we have said many times on CNiC, don’t require marathon duration or rigor. Walking is enough. And many employers subsidize gym memberships or arrange discounts, including mine. But you shouldn’t have to leave work to get a little walk in - making stairwells attractive is one way and the suggestion Thaler focuses on. In our conglomerate of old and new buildings, my workplace has lots of unattractive stairwells that are often hard to find. At a previous job, I had the privilege of sitting on a committee that was thinking about how to design a new hospital building and one of the most compelling ideas I heard was to make the stairwells front and center - highly visible and the easiest choice (instead of pushed off into the corner and behind a heavy metal door). One of our newest buildings on campus, which also serves as the home to our outpatient cancer care, has a lovely open stairwell at one end of the building, easily visible from the entrance. I enjoy seeing staff using the stairs and leaving the elevators to our patients, many of whom aren’t well enough to climb the stairs to the upper floors of the building. As we embark on a series of renovations and construction of new facilities as part of the 10 year plan, I look forward to seeing how our leadership makes stair use an easy option. In addition, our campus has launched a series of paths around the area (affectionately called “Tread the Med”) to allow staff and visitors to take walking breaks or have walking meetings (as Thaler plans to do in 2012). We have often used these exact “paths” around campus for our walking interventions during inclement weather and they are a great resource. I applaud the leaders who thought to leverage the bridges and hallways that link our conglomerate of old buildings as a means to promoting activity! Combined with easily located, accessible and attractive stairways, our step counts on campus should continue to rise.

Since most Americans spend more waking hours at work than at home, the role of our employers and workplaces at making healthy choices easy (or at least easier) can’t be underestimated. As part of our new TREC @ WUSTL center, our colleagues are examining just this - workplace policies that impact obesity, diet and physical activity.

Medical interventions to prevent cancer


Much has been written over the past few months on progress against cancer. For example, in the New York Times, Kolata summarizes funding for cancer research and shows the percentage of health research funding spent on cancer treatment research, cancer biology, and cancer causation, with only a small fraction on early detection and prevention (1).  This reflects the commitment made forty years ago, when the U.S. declared war on cancer, and promised a cure. While treatment and biology gain the predominant funding, we should remember that there are proven ways to prevent cancer, some through lifestyle changes, and others through medical interventions. While medical interventions may most often be focused on high-risk men and women, we know that smoking cessation – a population wide strategy – can reduce both incidence of many cancers and mortality from cancer. 

Smoking cessation powerfully reduces lung cancer and total mortality as demonstrated in Figure 1. Compared to continuing smokers, those who successfully quit have a 20% reduction in lung cancer mortality within 1 to 4 years of quitting and a 40% reduction within 5 to 9 years (2). Smoking cessation also reduces total mortality by 13% in less than 5 years and by 33% in less than 10 years, due to the additional benefits of reduced risk of cardiovascular death and other smoking-related cancer deaths (2). Thus, the benefits for smoking cessation are unarguable.

On the other hand, seeking technologic solutions, the randomized clinical trial for screening smokers with CT scans, showed a 20% reduction in lung cancer mortality after an average of 6 years of follow-up, and a reduction in total mortality of 6.7% (9).
        
But there are other research-proven strategies and interventions to prevent much of cancer outright.

We might consider these as drugs (aspirin, selective estrogen receptor modulators), vaccines, and screening or surgical interventions. While the time frame from intervention to benefit varies for the cancers, most of these medical interventions result in substantial benefits and typically the benefits outweigh the risks of exposing the population to the medical procedures. For example, we estimated that a large proportion of postmenopausal women would benefit from Raloxifene (a SERM) and given its relative positive trade off of benefits to risk, its widespread use could result in a substantial reduction in postmenopausal breast cancer (3). Likewise, for aspirin which is recommended for men over 45 to reduce risk of cardiovascular disease, and for women over 55 to reduce risk of cerebrovascular disease (4), the benefits for colon and other cancer risk reduction over 20 or more years of use are substantial (5). Perhaps the reduction in cancer is an unintended benefit of widespread use to reduce cardiovascular disease risk.

Vaccines, on the other hand, more typically considered a population-wide interventions, take decades to observe the benefit of reduced cancer incidence, and require broad implementation to achieve reduction in the cancer burden for the whole population. Several countries have embarked on more traditional public health strategies for HPV vaccine (Australia, mandatory) and hepatitis vaccine programs (e.g., Taiwan) to achieve reductions in the burden of cancer.

In the table below, we summarize the target for each intervention, the magnitude of reduction in cancer that has been observed following interventions, and the source of evidence for each intervention.


Table. Proven cancer prevention interventions using medical interventions
Intervention
Target
Magnitude of reduction
Evidence
Aspirin
Total cancer mortality
20% reduction
Follow-up of 8 RCT (5)
Aspirin
Colon cancer

40%
Five RCTs (6) and RCT in Lynch syndrome (7)
SERMs
Tamoxifen
Raloxifene
Breast cancer incidence
40 to 50%
RCT (8, 9)
Salpingo oophorectomy
Familial risk of breast cancer
50%
Observational data synthesis (10)
Screening for colon cancer
Sigmoidoscopy (RCT)
Colonoscopy
Colon cancer mortality
Sigmoiodoscopy 30% to 40% in 10 years

Colonoscopy – 50%
UK RCT sigmoidoscopy  (11)

observational data
Vaccines
HPV
Hepatitis, etc
Cervical cancer
Liver cancer

(12, 13)
Mammography
Breast mortality
30%
RCT refs
Spiral CT for lung cancer
Lung ca mortality
20% in 6.5 yrs
RCT (14)

Related CNiC posts


Smoking cessation: The rapid road to preventing cancer mortality 



Literature cited