Aim: The selective use of defunctioning stomas in anterior resection for rectal cancer hinges on accurately predicting anastomotic leakage. The aim of this study was to develop a prediction model for use in a prospective randomized clinical trial.
Method: Colorectal Cancer Database (CRCBaSe) Sweden was used to identify patients who underwent low anterior resection for rectal cancer 2007-2021. Eligibility criteria mirrored the forthcoming SELective defunctioning Stoma Approach in low anterior resection for rectal cancer (SELSA) trial, including patients <80 years of age and with American Society of Anaesthesiologists' (ASA) physical status grade of Results: Of the 2727 eligible patients, 199 (7.3%) were registered with an anastomotic leakage. All models demonstrated similar performance, with prediction instability observed for risks exceeding 12.5%. The preferred model included three significant predictors: male sex (OR 2.00; 95% CI: 1.45-2.75), BMI >30 kg/m2 (OR 1.82; 95% CI: 1.21-2.74), and radiotherapy (OR 1.90; 95% CI: 1.35-2.69). The bootstrapped area under the curve (AUC) was 0.64 (95% CI: 0.62-0.65), with a negative predictive value of 94.6% (95% CI: 93.7%-95.6%). For the validation cohort, the corresponding estimates were 0.66 (95% CI: 0.59-0.74) and 89.5% (95% CI: 86.2%-92.5%). Conclusion: Accuracy of anastomotic leakage prediction using registry-based data is moderate; however, the model's ability to rule out a >10% risk is considered appropriate for trial use. Keywords: anastomosis; diverting stoma; insufficiency; leakage; prediction; total mesorectal excision. © 2025 The Author(s). Colorectal Disease published by John Wiley & Sons Ltd on behalf of Association of Coloproctology of Great Britain and Ireland.
