Abstract
BACKGROUND: Accurate prediction of disease-free survival after radical resection in patients with pancreatic ductal adenocarcinoma (PDAC) remains challenging. Therefore, this study establishes and validates a predictive model for disease-free survival (DFS) after radical resection in patients diagnosed with PDAC. METHODS: This study gathered clinical and preoperative imaging characteristics of 258 patients with PDAC who underwent radical resection at our institution. The patients were randomly allocated into a training set (n = 218) and a validation set (n = 40) at an 8:2 ratio. Survival outcomes were analyzed using Kaplan–Meier survival analysis with the log-rank test. A nomogram was developed following univariate and multivariate Cox analyses. The performance of the nomogram was assessed using the concordance index (C-index), calibration curves, and decision curves analysis (DCA). An X-tile analysis was conducted to identify three risk groups. RESULTS: Body mass index, preoperative carbohydrate antigen 19 − 9 (CA19-9) > 1000 U/mL, N stage, superior mesenteric vein involvement, and superior mesenteric artery involvement were independent influencing factors of DFS (p < 0.05). Subsequently, a predictive nomogram was developed. The C-index of the model in the training set and validation set was 0.66 (95% confidence interval (95% CI): 0.64–0.68) and 0.60 (95% CI: 0.53–0.67), respectively, with calibration curves indicating good agreement. DCAs demonstrated the clinical utility of the nomogram model. Additionally, the nomogram classified patients into three distinct score groups (low, medium, and high). CONCLUSIONS: We successfully identified independent factors influencing DFS and developed a user-friendly and efficient prediction nomogram. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12880-026-02301-7.