Benchmarking the Learning Curve of Minimally Invasive Rectal Cancer Surgery Using Textbook Outcome: A Retrospective Analysis of Laparoscopic, Robotic, and Transanal Rectal Cancer Resections

Abstract Aim The Textbook Outcome (TO) is a valuable tool for benchmarking but has not been used to evaluate the early learning curve of minimally invasive rectal cancer surgery. This retrospective study compared TO over a 10-year period across four surgical approaches to TME—open surgery (OPEN), laparoscopic (LAP), transanal (TaTME), and robotic (ROB)—focusing on the early learning-curve phase. Methods We examined 684 patients who underwent minimally invasive rectal cancer surgery from January 2014 to July 2024. TO was defined using an 8-point scoring system assessing operating time deviation, intraoperative complications (ClassIntra), postoperative complications (Clavien-Dindo III-V), length of stay >14 days or readmission within 30 days, mesorectal completeness, CRM ≤1mm, distal resection margin ≤1mm, lymph node harvest <12. Regression analysis was used to compare early learning curves in TO across surgical approaches. Results Patient demographics were similar across the OPEN (n=153), LAP (n=341), TaTME (n=54), and ROB (n=135) groups. ROB demonstrated consistent TO ratings from the beginning, the shortest average operating time (208 min, SD 60, overall p<0.001), and the lowest rate of perioperative complications (overall p=0.013). Overall, there were no significant differences among the groups regarding postoperative complications. The highest quality of mesorectal excision was observed in the robotic group (TaTME: 67.3%; OPEN: 84.6%; LAP: 87.9%; ROB: 88.9%; overall p<0.001). TaTME experienced early learning curve challenges in achieving TO, with first year cases showing a higher postoperative complication rate (overall p=0.030) and no TaTME cases meeting operating-time targets in the first year (overall p=0.029), although this improved within two years. Conclusion During the early learning phase, TaTME faced performance challenges, whereas laparoscopic and robotic TME implementation showed positive initial learning-curve results. The TO can serve as a standardized benchmark for assessing the quality of the early learning curve. Conducting regular intrahospital quality control of TO will verify whether the surgical work is of satisfactory quality or identify any aspects of the surgical procedure that need adjustment to achieve better results.