Incorporating Obesity, Diabetes And Cancer Research Into Patient Care

Although diabetes and obesity do not cause cancer, they can make the prognosis worse for this condition. A recent presentation from EMI Live, a monthly educational conference from Cleveland Clinic’s Endocrinology and Metabolism Institute that is broadcast live across the nation and offers free CME to its participants, suggests that this occurs not because of high blood sugars, but rather because of high insulin levels. Vinni Makin, MD, an endocrinologist in Cleveland Clinic’s Endocrinology & Metabolism Institute and Director of EMI Live believes the research is convincing, but also notes that the findings are based on bench research with mice and meta-analysis of trials that show associations between diabetes or high cholesterol levels with cancer, and she cautions that there is a substantial difference between research and practical implementation in the community.

The research was presented by EMI Live’s inaugural speaker, Derek LeRoith, MD, PhD, the Director of Research in the Division of Endocrinology, Diabetes and Bone Disease at Icahn School of Medicine at Miami Sinai in New York. Dr. LeRoith discussed the epidemiology of obesity and diabetes and the increased risk for cancer. He pointed to several elegant studies done by his group showing that both obesity and type 2 diabetes have insulin resistance or hyperinsulinemia, which may be the primary factor for why cancer progression may be worse in patients with diabetes.

From theory to practice

“Dr. LeRoith has done a lot of research in trying to link diabetes and obesity with cancer,” notes Dr. Makin. “One of his proposals during his presentation was adjusting the number of regular cancer screenings that we do for patients. For example, should the current guidelines for colonoscopies over the age of 50 or mammograms over the age of 40 in women be adjusted? Patients with diabetes have a worse prognosis with these cancers. So, it is an interesting perspective in which he’s looking at bench studies and trying to make a connection with their clinical implications.”

However, Dr. Makin notes there are logistical concerns for what Dr. LeRoith is suggesting. “There are 34.2 million people in the U.S. with diabetes. If you start screening all of them with colonoscopies early, let’s say we start at 40 years old instead of 50, then you are looking at millions of extra colonoscopies a year. I don’t know if our health system can handle that. The studies also do not indicate that these cancer screenings are actually going to help prevent cancer or catch them early. The data he presented was very convincing but actually applying it in a community will need a close look at the costs and the logistics behind such change.”

Dr. LeRoith also discussed how diabetes medication can be incorporated into the treatment plan for patients with obesity and cancer. One of the drugs he points to, biguanides (Metformin), has been shown to reduce insulin levels without affecting glucose levels in breast cancer patients. However, it is not known why this occurs, and whether Metformin is solely reducing insulin levels or if it has a direct effect on cancer cells. Although Metformin is not a high-risk drug—the complications associated with the drug are infrequent—it has not been approved for cancer treatment. There are currently ongoing trials that might be able to answer the question in the future.

Dr. Makin also points out that many of our current large studies focus on diabetes and the cardiovascular benefits and risks of various drugs but not as much on the cancer risk of the disease and a possible protective effect of the medication. Cancer studies take a long time to accumulate enough data to actually make a difference, and Dr. LeRoith highlights that as well.

The treatment plan for our patients

Cleveland Clinic incorporates coordinated care into the treatment plan for its patients with diabetes and cancer. Anybody who has diabetes and is currently undergoing cancer treatments is seen much more frequently in the endocrinology clinics across the enterprise. Virtual visits are often used for these patients to decrease travel times and pandemic exposure, and they can be seen on a weekly or biweekly schedule. Patients, especially those who are on multiple diabetes medications, require active management because sugar levels tend to be associated with diet, activity or interfering medications. Diet and activity often fluctuate in cancer patients, depending on their stage of treatment or remission.

“In this pandemic era, we have perfected our virtual visit logistics,” says Dr. Makin. “We have ways to download patient devices remotely. If a patient is on insulin pumps or if they’re on continuous glucose monitors (CGM), we can see their data and make adjustments accordingly. We also have a program that is being piloted across the Cleveland Clinic enterprise, where we can have patients send in their CGM data and the pharmacist or the nurse practitioner can look at the blood sugar readings and adjust things very frequently.”

Because diet has such an integral role, patients also receive extensive nutrition counseling. Cleveland Clinic endocrinologists work closely with and often refer patients to nutritionists and diabetes educators. Dietitians within the endocrinology department are scattered all over the Greater Cleveland area to provide this service. One of the facilities features an obesity center with an exercise physiologist who focuses on exercise classes for patients who want to lose weight.

In his presentation, Dr. LeRoith brought up the Keto diet as being a potentially valuable tool, but he also mentioned apprehension because of associated side effects. With the Keto diet, patients can see a large amount of weight loss very quickly. However, Dr. Makin points out two concerns—long-term compliance and occasionally worsening cholesterol—that limit her proclivity to recommend it to her patients.

“In our practice, if patients need to lose weight for a procedure, such as a knee or hip replacement surgery, then I would probably suggest that they go on the Keto diet because we need them reach a target weight quickly and not have a prolonged wait for the surgery,” explains Dr. Makin. “On the other hand, if I have a patient whose goal is to lose weight without a quick deadline and become healthier, I would probably advise a less restrictive diet, something that is easier to stick to in the long run, and emphasize activity alongside to help build muscle.”