Constructing and validating a risk prediction model for postoperative bleeding after colorectal EMR in the Chinese population: a machine learning-based study
摘要
Endoscopic mucosal resection (EMR) is a minimally invasive treatment for early colorectal lesions. However, post-EMR clinically significant delayed bleeding (CSPEB) is a common complication affecting patient outcomes. Accurate risk prediction is essential for optimizing management and reducing complications.
MethodsWe conducted a retrospective study of 3888 patients who underwent colorectal EMR at Sun Yat-sen University’s Sixth Affiliated Hospital from January 2018 to September 2024. External validation was performed using data from 1000 patients at Shenzhen Hospital of Southern Medical University (2022–2024). CSPEB was defined as postoperative lower gastrointestinal bleeding requiring endoscopic intervention within 30 days. Risk factors were identified using logistic regression. A random forest model with weighted sampling was developed and evaluated using ROC curves, calibration plots, and decision curve analysis (DCA). The model was implemented in a web-based application.
ResultsCSPEB occurred in 1.4% of patients. Six independent risk factors were identified: sigmoid location, lesion size, number of lesions, APTT, fibrinogen, and hemoclip count. The model achieved an AUC of 0.87 ± 0.04 (sensitivity 71%, specificity 86%). External validation showed an AUC of 0.80 (sensitivity 61.5%, specificity 89.0%). SHAP methods enhanced model interpretability. Calibration and DCA confirmed strong predictive performance and clinical utility.
ConclusionWe developed and validated the first machine learning model for predicting post-EMR bleeding in the Chinese population. The model provides accurate, interpretable risk predictions and has been integrated into a user-friendly web tool to support clinical decision-making and improve patient outcomes.
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