How Safe Is Teaching of Complex Rectal Surgery? A Propensity Score-Matched 10-Year Cohort Study

Background Centralization of complex rectal surgery to specialized centers provides opportunities for supervised training. However, the impact of surgical teaching on outcomes in this highly specialized setting remains uncertain. Aims This study aimed to analyse the impact of an institutional teaching program of highly specialized rectal procedures on intra- and early postoperative outcomes. Methods This is a retrospective 10-year cohort study of consecutive patients undergoing low anterior resection or abdominoperineal resection for rectal cancer located within 12cm from the anal verge or restorative proctocolectomy with ileal pouch–anal anastomosis at a tertiary high volume academic center. Procedures were classified as expert (consultant-only) or teaching procedures (performed ≥75% by the trainee under direct supervision). Groups were balanced after 1:1 propensity score matching for patient characteristics. Primary outcomes were intraoperative surgical adverse events (IAEs) and 30-day complications. Multivariable logistic regression identified predictors of morbidity. Results A total of 573 surgeries were included. After matching, 374 remained (187 per group). IAEs occurred in 16% and 17% of expert-led and teaching procedures, respectively (p = 0.9). Overall morbidity was 43% vs. 46% (p = 0.7), severe complications (Clavien–Dindo ≥ IIIb) occurred in 16% vs. 17% (p = 0.9), while 30-day mortality was 1.1% vs. 0% (p = 0.5). Median hospital stay was 8 vs. 7 days (p = 0.6). Reoperation within 30 days occurred in 15.5% in both groups. Multivariable analysis revealed high comorbidity indices and immunosuppression as independent risk factors. Robotic surgery was independently associated with lower postoperative morbidity, while teaching was neither associated with overall morbidity (OR 0.60, 95% CI 0.30–1.17) nor severe complications (OR 0.64, 95% CI 0.26–1.48). Conclusion Closely supervised teaching of complex rectal surgery can be implemented into clinical practice without increasing perioperative morbidity, supporting the dual mission of surgical proficiency and training of high-volume centers.