Effectiveness of Preoperative Immunonutrition in Improving Surgical Outcomes after Radical Cystectomy for Bladder Cancer: Study Protocol for a Multicentre, Open-Label, Randomised Trial (INu-RC).

Radical cystectomy (RC) with pelvic lymph node dissection is the standard treatment for patients with limited-stage muscle-invasive bladder cancer. RC is associated with a complication rate of approximately 50-88%. Immunonutrition (IMN) refers to the administration of substrates, such as omega-3 fatty acids, arginine, glutamine, and nucleotides, that modulate the immune response. IMN has been associated with improved outcomes following surgery for esophagogastric, colorectal and pancreatic cancer. In this paper, we describe a study protocol for a multicentre, randomised, open-label clinical trial to evaluate the effect of IMN in patients undergoing RC for bladder cancer. A 7-day preoperative course of IMN is compared with a standard high-calorie high-protein oral nutritional supplement. The primary outcome of this study is the rate of complications (infectious, wound-related, gastrointestinal, and urinary complications) in the first 30 days after RC. Secondary outcomes include time to recovery of bowel function and postoperative mobilisation, changes in muscle strength and body weight, biochemical modifications, need for blood transfusion, length of stay, readmission rate, and mortality. The results of this study may provide new insights into the impact of IMN on postoperative outcomes after RC and may help improve IMN prescribing based on patient nutritional status parameters.