Perioperative Biomarkers in Colorectal and Gastric Cancer Surgery

Study Design and Objectives This study is a prospective, single-center, randomized controlled trial conducted at Bucharest Emergency Clinical Hospital, Romania, involving adult patients undergoing surgery for colorectal or gastric cancer. The primary objective is to investigate whether perioperative monitoring of inflammatory and metabolic biomarkers, integrated into postoperative care, can facilitate early identification of postoperative complications within 30 days after surgery. Randomization and Study Groups Eligible participants are randomly assigned to one of two study groups using stratified block randomization. Allocation is performed using sealed envelopes prepared independently of the investigator. The intervention group receives perioperative care incorporating Enhanced Recovery After Surgery (ERAS) principles and structured biomarker monitoring. The control group receives standard perioperative care without protocol-mandated postoperative biomarker monitoring. Biomarker Assessment The biomarkers evaluated include procalcitonin (PCT), blood lactate, and blood glucose. Preoperative assessment includes lactate, blood glucose, and serum electrolytes. Postoperative biomarker monitoring in the intervention group includes lactate and procalcitonin approximately 12 hours after surgery, followed by additional procalcitonin measurements on postoperative days 3, 5, and 7. Procalcitonin is assessed using a point-of-care semi-quantitative method. Clinical Outcomes Patients are followed for 30 days after surgery to assess postoperative complications, including surgical site infections, anastomotic leakage, and other infectious or non-infectious complications. Additional outcomes include postoperative mortality, hospital length of stay, and hospital readmissions. Clinical and laboratory findings will be analyzed to explore associations between perioperative biomarker patterns and postoperative outcomes and to evaluate the potential clinical usefulness of biomarker-guided postoperative monitoring. Ethical Considerations The study was approved by the hospital's Ethics Committee (Approval No. 46148, dated October 27, 2025). Written informed consent is obtained from all participants before enrollment.