September 09, 2026
Thirteen years ago, Jill Hamilton-Reeves, PhD was a board-certified oncology nutritionist at the University of Kansas Medical Center when Jeffrey Holzbeierlein, MD, a urologist, told her about a patient he was treating for bladder cancer. Since undergoing a radical cystectomy, surgical removal of the bladder, the patient had inadvertently lost 40 pounds, even though the surgery had gone well. Dr. Holzbeierlein told Dr. Hamilton-Reeves that substantial weight loss, which includes muscle loss, happens in a subset of these patients, but it isn’t clear why. Such significant weight loss is associated with other complications well as higher death rates.
Dr. Hamilton-Reeves then did some of her own research and learned that close to two-thirds of patients that have a cystectomy have a post-surgical complication, and one in four get an infection. While this surgery remains part of the standard of care for muscle-invasive bladder cancer, physicians have struggled to reduce complications. “Despite multiple interventions from surgeons across the world, we haven't been able to change complication rates much at all,” said Dr. Holzbeierlein, professor of urology at KU School of Medicine and physician in chief at The University of Kansas Cancer Center.
Dr. Hamilton-Reeves, who also conducts translational science — turning observations in the laboratory and clinic into interventions that improve health — immediately looked at the problem through the lens of her nutrition background. “I thought, if people are malnourished going into this, that's going to make them more susceptible to infections as well as some of the other complications commonly seen with this surgery,” remembered Dr. Hamilton-Reeves, now a professor in the Department of Urologic Surgery, a member of the cancer center’s Obesity, Metabolic Health and Cancer research program, and an educator in the Department of Dietetics and Nutrition at KU School of Health Professions.
A radical cystectomy is a complex procedure that involves removing the bladder, nearby lymph nodes and adjacent pelvic organs including the prostate, uterus, ovaries and fallopian tubes. Using a piece of the small intestine, the surgeon then constructs a new way for the body to store and pass urine. In addition to infections, common complications after surgery include blood clots, bowel obstruction and ileus, a temporary condition during which the intestines do not function properly.
There was some data showing that if people were malnourished before surgery, they had worse outcomes. Dr. Hamilton-Reeves proposed conducting a study to see if giving bladder cancer patients a specialized immunonutrition drink three times a day, for five days before and after surgery, could reduce the rate of infection. This drink had been shown to reduce complications in colon cancer patients. The drink contained omega-3 fatty acids, which help manage inflammation, as well as dietary nucleotides, which help the body rebuild immune cells to fight infection. The drink also contained l-arginine, an amino acid that can become deficient in patients after surgery.
This pilot study, with 29 participants, found that those who received the immunonutrition supplement with the extra nutrients had fewer complications, including fewer infections, after 90 days, than those who received a standard oral nutrition supplement. The results were promising, Dr. Hamilton-Reeves said, but the study size was small.
Dr. Hamilton-Reeves then got competitive funding from the National Institutes of Health (NIH) and support from SWOG (formerly the Southwest Oncology Group), a National Cancer Institute-supported organization that conducts clinical trials in adult cancer, to conduct a larger trial. The trial enrolled 203 participants at 13 sites across the country from 2019 to 2023. The participants were randomized to receive either the immunonutrition oral supplement or the standard oral nutrition supplement. Each supplement type had the same base formula; the only difference was that the immunonutrition supplement also contained the added omega-3 fatty acids, nucleotides and l-arginine.
The results, which were published in JAMA Network Open in July, found no statistically significant difference in post-operative infections and other complications between the two groups. “Even though it was so striking in our pilot study here at KU, when we ran this study across the country, we did not see that big difference in postoperative complications,” said Dr. Hamilton-Reeves.
She noted that one complicating factor was that the study happened during the pandemic, and that researchers had no way of knowing how many people either had COVID-19 around the time of the trial or had long COVID after. “That's a big unknown that I don't think we'll probably be able to answer,” she said.
However, the study also had one promising result: Although the specialized supplement did not reduce complications, the survival rate was higher for the group that received it. Two-year overall survival was 87.4% for those receiving the immunonutrition supplement versus 78.2% for the group receiving the standard nutrition supplement. Disease-free survival was 77% for the group receiving the immunonutrition supplement versus 67.5% for those receiving the standard nutrition supplement. Although these results were not statistically significant, the researchers believe they warrant more study, and three-year survival data are to come.
“We are now using our science and our collaborations to better understand what was happening and if we can leverage that to create better interventions,” said Dr. Hamilton-Reeves.
To do so, they will look at immune cells, metabolism, the microbiome and patient nutrition status.
Dr. Holzbeierlein emphasized the importance of such translational science in solving a clinical problem.
“What Dr. Hamilton-Reeves has done really well is to take our clinical observations and explain those through basic science,” he said. “When a clinician has a problem that they don't understand, a basic researcher can use their expertise to try and elucidate the cause, which can lead to solutions.”
This article originally appeared on the University of Kansas Medical Center's website.