RETROCOLIC TUNNEL VERSUS CONVENTIONAL MEDIAL TO-LATERAL APPROACH IN LAPAROSCOPIC RIGHT HEMICOLECTOMY WITH COMPLETE MESOCOLIC EXCISION: COMPARATIVE COHORT STUDY AND CUSUM LEARNING-CURVE ANALYSIS

Abstract

Background: Laparoscopic right hemicolectomy with complete mesocolic excision (CME) entails careful embryological-plane dissection and central vascular control. Retrocolic tunnel dissection may provide early orientation and safer access to the superior mesenteric vascular axis, but comparative data and technique-specific learning-curve assessment remain limited. Objective: To compare perioperative safety, pathological adequacy and early recovery after retrocolic tunnel versus conventional medial-to-lateral laparoscopic right hemicolectomy, and to evaluate procedural proficiency using cumulative sum (CUSUM) methods. Methods: A comparative cohort design was conducted in the Surgery department at General Hospital Lahore from January 2025 to January 2026.Consecutive adults undergoing elective laparoscopic right hemicolectomy with CME. A minimum of 84 participants (42 per arm), with a recruitment target of 96–100, is proposed. The primary outcomes are operative duration, blood loss, conversion to open surgery, lymph-node retrieval and mesocolic specimen quality. Secondary outcomes include vascular injury, recovery milestones, hospital stay, 30-day morbidity and learning-curve change points. Regression, propensity-based sensitivity analysis, chronological CUSUM and risk-adjusted CUSUM was performed. Results: To demonstrate statistical reporting, Tables 1–3 contain explicitly hypothetical group summaries for 50 patients per arm, with p values computed using Welch independent-samples t-tests or Fisher exact tests. Tables 4–5 use a separately generated synthetic patient-level dataset for demonstration only; model and change-point values Conclusion: The protocol provides an operational framework for evaluating whether retrocolic tunnel dissection improves technical efficiency while maintaining CME quality. Any superiority or equivalence claim must await completed analyses. Keywords: complete mesocolic excision; laparoscopic right hemicolectomy; retrocolic tunnel; medial-to-lateral; CUSUM; learning curve.