Extracapsular tumor spread does not influence survival outcomes in resected N1-patients with intrahepatic cholangiocarcinoma : a retrospectively controlled cohort study

Abstract

Background Extracapsular tumor spread (ECS) in lymph nodes is a known predictor of recurrence and decreased survival across various malignancies, including breast and head and neck cancers. However, its prognostic value in patients with intrahepatic cholangiocarcinoma (iCCA) undergoing curative surgery has not yet been explored. Methods A retrospective cohort study was conducted, including all patients with lymph node-positive disease (N1) who underwent curative resection for iCCA between 2008 and November 2023. Patients were followed up for at least one year postoperatively. Cases with ECS-positive lymph nodes (N1/ECS+) were compared to those without extracapsular tumor infiltration (N1/ECS-). Statistical analyses included the T-test for continuous variables and the Chi-square test for categorical variables. Survival outcomes were evaluated using the Kaplan-Meier method. Results 70 patients with N1 disease following potentially curative resection were included. Baseline characteristics were comparable between groups (N1/ECS + n = 30, N1/ECS- n = 40), with no significant differences in age (p = 0.853), resection type (p = 0.511), T-stage (p = 0.785), resection margins (p = 0.687) or the number of tumor-positive lymph nodes (p = 0.052). The median overall survival (OS) was 17.2 months in the N1/ECS + group and 17.3 months in the N1/ECS- group (p = 0.466). Similarly, recurrence-free survival (RFS) was not significantly different, with a median of 4.4 months for N1/ECS + patients versus 7.7 months for N1/ECS- patients (p = 0.335). Conclusion Extracapsular tumor spread in lymph nodes was not associated with significant differences in overall or recurrence-free survival in patients with intrahepatic cholangiocarcinoma undergoing curative resection. Based on these findings, ECS does not appear to serve as a prognostic predictor of outcomes in this population.