As scientific advances in cancer care save more lives, attention is increasingly being focused on helping patients and survivors adopt lifestyle behaviors that promote health. The National Cancer Policy Forum (NCPF) of the National Academies of Sciences, Engineering, and Medicine held a workshop meeting in Washington, D.C., to discuss opportunities and challenges in incorporating interventions in weight management and physical activity to foster healthy lifestyles throughout the cancer continuum. A report from the workshop will be forthcoming.
The meeting raised some of the following questions: What is the evidence that supports weight management and physical activity for cancer patients and survivors? Why are oncologists slow to refer cancer patients to weight management and exercise programs? What program models are most effective? Should such programs be cancer-specific? Is there insurance reimbursement for these programs?
The Impact of Being Overweight
A major focus at the NCPF workshop was the high levels of overweight and obesity in the U.S. Up to 71 percent of adult cancer survivors are overweight or obese, said Workshop Chair Wendy Demark-Wahnefried, PhD, RD, Professor and Webb Endowed Chair of Nutrition Sciences at the University of Alabama at Birmingham (UAB). In addition, "Almost all studies of individuals diagnosed with cancer show adverse body changes over time as compared to controls," noted Demark-Wahnefried, who is also Associate Director for Cancer Prevention and Control at UAB Comprehensive Cancer Center. These changes may include loss of lean muscle mass and an increase in body fat.
"We know we're in the midst of an obesity epidemic," said Pamela Goodwin, MD, MSc, who leads the Hold'Em for Life Translating Research Discoveries into Breast Cancer Cures Program at Mount Sinai Hospital and the Princess Margaret Cancer Centre, Toronto. For many of the common cancer types, being overweight or obese raises cancer risk, said Goodwin.
"This is an association; we don't know if it's causal," she said. "I believe that it is a true association." She noted that increased fat mass can lead to altered physiology, which can have an impact on cancer in a number of ways, including elevated inflammatory markers and elevated insulin levels.
According to the National Comprehensive Cancer Network, "There is evidence that being overweight, which is a risk factor for numerous types of cancer, also increases the chance of recurrence and lowers odds for survival." This evidence appears to be strongest for early-stage breast cancer and prostate cancer. Goodwin cautioned that, while it is known that being of normal weight can reduce the risk of developing many cancer types, as of now it is not definitively known whether loss of weight through exercise and healthy eating can reduce the risk of recurrence in overweight or obese cancer survivors. She noted that controlled clinical trials that track cancer outcomes will be essential to conclude that physical activity and dietary interventions can help cancer survivors lower their risk of recurrence. But, she said, "What we can say is that these interventions will improve the quality of life and general health of our patients."
"The data show that being skinny lowers cancer risk and that being fat raises cancer risk," said NCPF member and American Cancer Society Chief Medical Officer Otis W. Brawley, MD, when asked for comment by Oncology Times. But, he said, data on the effect of weight and the risk of cancer recurrence are much less clear than data on the effect of weight and the initial cancer diagnosis. Brawley agreed with Goodwin that weight loss for obese patients should be advocated for quality of life and general health. But, he noted, "It is so hard to lose weight," and cancer patients and survivors should not be made to feel guilty if they cannot shed unwanted pounds.
Healthy Ways to Prevent Cancer
As far back as 2007, a massive report from the World Cancer Research Fund and the American Institute for Cancer Research, Food, Nutrition, Physical Activity and the Prevention of Cancer: a Global Perspective, included recommendations for cancer survivors as well as for prevention of cancer. The recommendations state that all cancer survivors should "receive nutritional care from an appropriately trained professional," and that "if able to do so, and unless otherwise advised," they should aim to follow the same general recommendations for diet, healthy weight, and physical activity given to prevent cancer.
"I think exercise truly is a form of precision medicine," said Marcas Bamman, PhD, Professor in the University of Alabama at Birmingham Departments of Cell, Developmental, and Integrative Biology, Medicine, and Neurology and Director of the UAB Center for Exercise Medicine. "I would argue that exercise is regenerative medicine," Bamman added, pointing out that "Exercise profoundly impacts the integrity and function of every major organ system and is, therefore, considered the only pluripotent form of medicine available."
Although more research is needed, some studies have shown that cancer survivors who report the highest levels of exercise have about a 37 percent lower risk of dying from cancer during follow-up, said Kerry S. Courneya, PhD, Professor and Canada Research Chair in the Faculty of Physical Education and Recreation at the University of Alberta, Canada. But researchers have to be open to the possibility that some vigorous exercise workouts could worsen certain cancers, cautioned Courneya, who is study Co-Chair for the multinational Colon Health and Life-Long Exercise Change (CHALLENGE) Trial-the first phase III trial designed to determine the effects of exercise on disease-free survival in 962 colon cancer survivors. He is also actively involved in studies of exercise and survival in advanced prostate cancer and breast cancer.
Many cancer patients are older because the incidence rates rise with age for many cancers, and healthy lifestyle interventions may be especially helpful for them, said Melinda Irwin, PhD, MPH, Professor of Epidemiology in the Yale University School of Public Health, Associate Director for Population Sciences in the Yale Cancer Center, and a co-leader of the Cancer Prevention and Control Research Program within the Yale Cancer Center. Irwin said exercise for these patients may help combat fatigue, improve completion of chemotherapy regimens, raise the fitness level, improve sleep, and reduce lymphedema symptoms and joint pain. "Maintaining functional independence as we age is a priority," she noted.
"Obesity and inactivity are associated with poor prognosis in many cancers," stressed Jennifer Ligibel, MD, Senior Physician in Medical Oncology in the Susan F. Smith Center for Women's Cancers at Dana-Farber Cancer Institute, Director of the Leonard P. Zakim Center for Integrative Therapies at Dana-Farber, and Assistant Professor at Harvard Medical School, Boston. She said there are randomized clinical trials underway studying weight management and disease recurrence or mortality in breast, ovarian, colon, and prostate cancers. Results from these trials should help to build a solid data base in this area.
Patient advocate Robert Harrison, a metastatic prostate cancer survivor in Clayton, N.C., told meeting attendees he was overweight, but after connecting with an exercise physiologiy program via Skype, he lost 60 pounds and feels good. "There's no limit to what I can do. It's a mindset; it's not a program," said Harrison, founding President of the Patient and Family Advisory Board at the North Carolina Cancer Hospital in Chapel Hill. "This is not rocket science...we can do this, we must do this, and we should do this," he emphasized. Harrison said his oncologist told him his exercise program has been as effective in his cancer care as the treatments he is taking.
Advancing Patient Programs
But, in general, oncologists have been slow to refer cancer patients and survivors to weight management and exercise programs, said speakers. "Oncologists have to do many things, and they have to do what they're good at," said Goodwin. Oncologists want to know that if they do refer, it will be to a person or program they trust because it isn't their area of expertise, she added. Stronger data on the link between exercise/lifestyle change and lowering the risk of recurrence could boost such referrals, according to speakers.
Such lifestyle change programs already exist and are serving many cancer patients, said Matt Longjohn, MD, MPH, National Health Officer and Vice President for Evidence-Based Health Interventions and Community Integrated Health at YMCA of the USA (Y-USA). One example is LIVESTRONG, a 12-week exercise program offered free of charge or at low cost in Ys across the country through support from the LIVESTRONG Foundation to help adult cancer survivors (the majority of whom are breast cancer survivors) regain their health. "We're trying to find that middle ground between evidence-based practice and practice-based evidence," said Longjohn.
LIVESTRONG participants report an improvement in quality of life, fitness, balance, strength, and flexibility, and a decrease in fatigue, said Longjohn. The YMCA was successful in gaining third party coverage for its Diabetes Prevention Program (DPP), and that "is the path we intend to follow for LIVESTRONG," noted Longjohn. Medicare coverage for the DPP is expected in January 2018. He added that the core of behavioral intervention programs such as the DPP and LIVESTRONG is the current trend toward community-integrated health services.
Making a compelling reimbursement case for exercise programs for cancer survivors is "a business and political problem," not a medical problem, said Darshak Sanghavi, MD, Chief Medical Officer and Senior Vice President of Translation at OptimumLabs. "Do you want to wait 5 or 10 years [for more data] or do you feel comfortable putting your money where your mouth is?" asked Sanghavi, former Director of Preventive and Population Health at the Center for Medicare and Medicaid Innovation within the U.S. Department of Health and Human Services (HHS).
One problem in trying to gather data on the value of exercise for cancer survivors is that research on exercise lacks the money the pharmaceutical industry has for trials on drugs, said Anand Parekh, MD, MPH, Chief Medical Advisor for the Bipartisan Policy Center and former Deputy Assistant Secretary for Health at HHS from 2008 to 2015. "Payers are really all over the map" when it comes to covering weight management behavioral interventions, and better assessment is needed. "That whole area of quality metrics needs to happen," he noted.
In addition to insurance coverage, other factors are important in ensuring high-quality exercise and lifestyle-change programs for weight management in cancer survivors are offered, studied, and evaluated, said Kathryn Schmitz, PhD, MPH, Professor of Public Health Sciences and Associate Director of Population Sciences at Pennsylvania State University's College of Medicine. Schmitz, who has led multiple trials including the Physical Activity and Lymphedema (PAL) trial, said these factors include:
* doing a better job of triaging patients to exercise programs, including safety-screening;
* making sure oncologists know about such programs, trust them, and have the time to make referrals;
* making the referral process as easy for clinicians as possible; ensuring that such programs have active follow-up; and
* cultivating champions of such programs among clinicians, who are crucial for program acceptance and implementation.
In the case of the NCI-funded PAL trial, she noted, the data show that the program cut the risk of lymphedema flare-ups in half, and PAL participants reported having an improved body image.
Peggy Eastman is a contributing writer.