As an internal medicine physician, sometimes I feel like I am playing whack-a-mole. At a time when tobacco use has been declining for decades, which has contributed to a sharp decline in lung cancer deaths, the obesity rates have soared-so much so that obesity now has emerged as a leading risk factor for a growing number of cancers. This helps explain why obesity is on the verge of overtaking tobacco as the leading cause of preventable cancer.
An estimated 84,000 cancer diagnoses annually are attributed to obesity (J Clin Oncol 2014; doi:10.1200/JCO.2014.58.4680) and researchers now have linked it to twelve types of cancer. Being overweight or obese increases the risk of breast cancer 20-40 percent, colorectal cancer 30 percent, and gallbladder cancer 20-60 percent. People who are overweight or obese are nearly twice as likely to develop cancers of the esophagus, gastric cardia, liver, and kidney. In addition, obese patients are likely to have other co-morbidities, such as diabetes, joint pain, and heart disease, which makes cancer treatment even more difficult.
While most of us who treat cancer patients are aware of the link between obesity and cancer, the public is not. ASCO's National Cancer Opinion Survey taken in July 2017 showed 78 percent and 66 percent of respondents correctly identified tobacco use and sun exposure as risk factors, but only 31 percent correctly identified obesity as a risk factor for cancer (Oncology Times 2017; doi:10.1097/01.COT.0000528025.42664.a2).
As a health care community, we must do more to educate the public about this risk-and the poorer outcomes that obese cancer patients have, which can seriously affect the quality and duration of life. For example, studies show that 5 years after the diagnosis of breast cancer, patients who are able to maintain a healthy weight are both less likely to have had a recurrence of breast cancer and less likely to develop a recurrence of breast cancer in the following years. While more than 80 percent of women with breast cancer become long-term survivors, we see a dramatic reduction in that number among those who are morbidly obese-just about 50 percent are long-term survivors.
So how should we tackle this problem? Let's start with what we know.
First, we know what doesn't work-healthy living and healthy lifestyle programs and public health warnings. We've tried them for decades, yet the obesity rate in this country continues to climb. The CDC reports that 93 million U.S. adults and roughly 14 million children are obese today.
We also know that the obesity and overweight issue is not tied to one or several specific generations, but is instead multi-generational. The rates are high among the elderly, Baby Boomers, Gen X, Gen Y, Millennials-the pattern keeps repeating itself, generation after generation.
If mass marketing of healthy lifestyles doesn't work, and virtually each generation has its own obesity problem, then the solution may be to think smaller and in a more focused manner-working with each of our patients, one patient at a time. Whether you are a primary care physician, a diabetes nurse educator, a nutritionist, or a fitness instructor, you should be taught the basic facts about obesity and cancer, and you should be trained in how to speak about these issues with patients. Obesity and cancer should be part of every provider's medical education and training. One by one, each of us must have the information, the confidence and, frankly, the courage to discuss weight management with overweight and obese patients in an open, respectful manner.
Second, health care providers need a simple message that we can keep delivering over and over to our patients, something along the lines of, "if you can get control of your weight, we have a better chance of getting control of your cancer." The message should be one of positivity and empowerment, not of criticism.
Third, we need more research into which, if any, weight loss programs are the best and for which patients. No two patients are the same, so it only makes sense that programs will work differently with different patients. As a community, we should evaluate if and when it is appropriate for cancer patients to undergo surgery, i.e., gastric bypass, as part of their treatment plan. Gastric bypass has become less complicated and more widely accepted in recent years, and it has the potential to extend survival for certain cancer patients, assuming it is accompanied by lifestyle changes that enable the patient to keep weight off on a sustainable basis.
In essence, I am advocating for us all to treat the whole patient and not just the cancer, and to integrate lifestyle counseling into our treatment plans. And I am calling for a 360-degree approach from the entire health care community-to ensure that all health care professionals are on the same page in interacting with their patients about the risks that come with obesity. For most of us, this is at odds with what we've been taught and how we've been trained. At the same time, however, it is very much in keeping with the philosophy of engaging the patients in having a say in their treatment plan, and empowering them to make a difference in their own lives. This integrated, patient-centric approach is our best hope in convincing patients to help us help them in their fight against cancer.
ANTHONY PERRE, MD, is Chief of the Division of Outpatient Medicine at Cancer Treatment Centers of America in Philadelphia.