Could cancer patients benefit from temporarily eating less? UB pilot studies aim to find out

A UB scientist has launched two pilot studies that focus on how dietary interventions might affect cancer treatment. One study will determine if patients on chemotherapy do better when they eat less just prior to treatment days and if they follow a plant-based diet.

The second pilot study will assess whether low protein meals may help the immune system. This study may be the only one in the country focusing on a specific dietary intervention for patients undergoing immunotherapies for cancer.  

Open to patients currently undergoing chemotherapy or immune therapies for any cancer, the studies are a first step in finding out how dietary interventions may impact how tumors respond to treatment. These dietary interventions also may reduce the side effects of chemotherapy.

The studies are currently enrolling 30 patients each. More information on the studies is at clinicaltrials.gov. Patients interested in participating can call 716-878-3317.

“The double goal of our studies is to improve the efficacy of therapies and perhaps to reduce the side effects from treatment,” said Roberto Pili, MD, principal investigator,  associate dean for cancer research and integrative oncology and chief, Division of Hematology and Oncology in the Jacobs School of Medicine and Biomedical Sciences at UB. “We want to know, can lifestyle interventions help patients on cancer treatment do better?”

Pili is inaugural director of UB’s new Sciences, Nutrition and Cancer (SNAC) Center, which is establishing a program for integrative oncology, where dietary interventions, exercise and mind-body medicine are integrated into cancer patient care.

Pili noted that there is scientific evidence that calorie restriction while patients are undergoing chemotherapy may improve their response to treatment. One small study on women with breast cancer who underwent calorie restriction for a few days prior to chemotherapy before surgery had a higher response rate to their treatment than those who didn’t undergo calorie restriction.

“Calorie restriction was initially proposed to ameliorate side effects from chemotherapy,” explained Pili, noting that a number of studies have shown that patients who fast the day before chemotherapy may experience less nausea and vomiting.

But an even more critical advantage was observed in a recent study showing that calorie restriction also made chemotherapy more effective, allowing patients to have an improved response to treatment.

“In one case we followed, a woman with breast cancer who agreed to undergo calorie restriction and a plant-based diet during chemotherapy prior to surgery achieved a complete response,” he said. “That means once they removed the breast tissue and tested it, they could not find any evidence of cancer. With the restriction in calories, the chemotherapy was able to completely destroy the cancer.”

Pili said that kind of response from conventional chemotherapy prior to surgery is achieved only in about 20-30% of breast cancer patients.

“With calorie restriction and a plant-based diet, we want to see if we can increase that response rate,” he said. “If it’s a 20% response rate, can we increase it to 30-40%? Could we boost that number so that more patients achieve a complete response to treatment?”

Patients enrolling in the study would limit their calories every other day, starting a few days before each chemo treatment, under the direct supervision of Colleen Barrientos, registered dietician and nutritionist and a medical student in the Jacobs School, and Kyle Pasquariello, clinical oncology research coordinator in the Department of Medicine and research coordinator with General Physician, PC.

For example, if a patient has chemotherapy on a Wednesday, then calories would be restricted on the previous Friday, Sunday and Tuesday, and also on the day of treatment, Wednesday. The patient would resume a normal diet in terms of calories after the chemo administration but would remain on the plant-based diet.

Pili noted that patients who enroll will need not only to be motivated to participate, but they will also need significant support from their families. He stressed that significant scientific evidence demonstrates that patients should see a benefit.

“Normal cells are more resilient to glucose starvation,” he explained, “but tumor cells are more sensitive to a lack of glucose, so they will be more vulnerable to the additional insult of chemotherapy. Cancer cells do not handle stress well, so they may be more vulnerable to concomitant chemotherapy and calorie restriction.”

The potential advantage of plant-based diets is based on what is known so far about the effects of lower animal protein consumption on the incidence of certain cancers, such as prostate cancer 1.

“Based on our preclinical studies, we propose a low protein diet for a couple of immunotherapy cycles,” he said. “It seems that the low protein diet primes the immune system, and once primed, it is easier to maintain the immune response with drugs. The low protein diet helps wake up the body’s immune response.”

Results from these preliminary studies are expected within 2 to 3 years.

“These are the frontiers of integrative oncology,” Pili said of the pilot studies, noting that it’s a frontier that requires a multidisciplinary approach.

“UB has all the expertise in place to bring together people from so many different disciplines, to deliver the personalized medicine and to personalize the lifestyle changes that can make each patient diagnosed with cancer have a better outcome,” he said. “This is not just a promise, it’s becoming a reality.

“We know that the body has so many resources that if we leverage them, we will be able to achieve the best results from therapy and, ultimately, defeat cancer,” he said.

The study is being funded by the Jacobs School and Kaleida Health through the Great Lakes Cancer Care Collaborative.