Abstract: Objective To establish a prediction model of delayed postpolypectomy bleeding (DPPB) after endoscopic submucosal dissection (ESD) in elderly patients with early gastric cancer, and to propose targeted prevention and treatment strategies. 
Methods A total of 936 patients with early gastric cancer diagnosed and treated in the First Affiliated Hospital of Nanjing Medical University and Nanjing Central Hospital, Jiangsu Province, from January 2020 to December 2023 were retrospectively included as research subjects. According to occurrence of DPPB, early gastric cancer patients were divided into the DPPB group (n=78, 8.33%)and the non-DPPB group (n=858, 91.67%). Multivariate Logistic regression was used to analyze the risk factors of DPPB after ESD, a prediction model was established, and the discriminatory degree of the model was evaluated by using the receiver operating characteristic (ROC) curve. 
Results Compared with the non-DPPB group, the DPPB group had a significantly higher proportion of age ＞75 years, history of hypertension, history of long-term antithrombotic drug use, gastric fundus-cardia tumor, tumor diameter ＞40 mm, duration of operation ＞60 min, and significant intraoperative bleeding, showing significant difference (P＜0.05). Multivariate Logistic regression analysis showed that age ＞75 years (OR=1.551, 95%CI: 1.058-2.273), tumors at the gastric fundus-cardia (OR=1.799,95%CI: 1.275-2.538), tumor diameters ≥40 mm (OR=2.776,95%CI: 1.264-6.098), significant intraoperative bleeding (OR=3.800, 95%CI: 1.651-8.745), and a history of long-term antithrombotic drug use (OR=2.643, 95%CI: 1.382-5.054) were independent risk factors for DPPB after ESD in patients with early gastric cancer. The risk of DPPB after ESD in patients with early gastric cancer C-index=-2.596+0.439×(age)+0.587×(history of long-term antithrombotic drug use)+1.021×(tumor site)+1.335×(tumor diameter)+0.972×(significant intraoperative bleeding). The ROC curve showed that the area under the curve (AUC) of the C-index in identifying the risk of DPPB after ESD in patients with early gastric cancer was 0.873 (95%CI:0.821-0.926), with the sensitivity of 85.90%, the specificity of 79.84%, and the accuracy of 80.34%. 
Conclusion The model established based on age, tumor site, tumor diameter, significant intraoperative bleeding, and history of long-term antithrombotic drug use can predict the risk of DPPB after ESD in patients with early gastric cancer, thus assisting the clinical identification of high-risk groups and targeted intervention. 

Key words: stomach neoplasms, endoscopic mucosal resection, postoperative bleeding, prediction