Development and External Validation of a Nomogram Predicting Early Recurrence of Gallbladder Cancer Using Preoperatively Available Prognosticators: A Korean Multicenter Retrospective Study

<b>Background:</b> Gallbladder cancer (GBC) is a rare and aggressive malignancy with poor prognosis and high recurrence rates, even after curative surgical resection. Early recurrence, defined as recurrence within one year after surgery, remains a major clinical concern. This study aimed to identify preoperative prognostic factors and develop a predictive model for early recurrence and overall survival in resected GBC patients. <b>Methods:</b> We retrospectively analyzed data from 251 patients who underwent curative-intent resection for GBC between 2008 and 2017. Logistic regression was used to identify preoperative factors associated with early recurrence. Significant variables were used to construct a nomogram, which was externally validated using a cohort of 176 patients from three independent tertiary centers. <b>Results:</b> The independent predictors of early recurrence included male sex, chronic liver disease, preoperative symptoms, elevated carcinoembryonic antigen (CEA), sarcopenic obesity, clinical T3 or higher stage, and suspected metastatic lymph nodes. The nomogram demonstrated strong predictive performance with an AUC of 0.872 (95% CI: 0.817-0.927) in internal validation and 0.703 (95% CI: 0.613-0.793) in external validation. <b>Conclusions:</b> We developed and externally validated a novel nomogram that predicts early recurrence in GBC using only preoperative factors. This model may support individualized risk assessment and aid surgeons and patients in shared decision-making prior to high-risk surgery.