Specialized immunonutrition may provide a way to improve immune response and decrease infection rates after radical cystectomy (RC), according to a small pilot study.
Infections account for up to 25% of postoperative complications at 30 and 90 days, a research team led by Jill M. Hamilton-Reeves, PhD, RD, of the University of Kansas Medical Center in Kansas City, noted in a report published online ahead of print in European Urology. Post-RC accumulation of myeloid-derived suppressor cells (MDSCs), which suppress T cells, may contribute to lower resistance to infection, they explained. In addition, surgery-induced arginine deficiency impairs lymphocyte proliferation and T-cell receptor integrity. The researchers hypothesized that arginine-enriched specialized immunonutrition (SIM) will modulate the immune response to surgery.
Dr. Hamilton-Reeves and her colleagues randomly assigned 29 men scheduled to undergo RC for primary bladder cancer to receive an arginine-enriched SIM beverage or an oral nutrition supplement (ONS, control arm) beverage before and after surgery. The primary study endpoint was the change in total MDSC counts.
The researchers observed a significantly smaller difference between MDSC counts at baseline and postoperative day 2 in the SIM group versus the ONS group. The change in MDSC counts during surgery (3 hours after the first incision) and postoperative day 2 was significantly less in the SIM group than the ONS group, according to the investigators. In addition, patients in the SIM arm experienced a significant 39% decrease in infection rate compared with the control group at 90 days after surgery.
The researchers acknowledged that the study was limited by the small sample size.