Abstract
BACKGROUND: Recent studies addressing the role of adjuvant chemotherapy (AC) in cholangiocarcinoma (CCA) have been published; however, there are challenges in generalizing the findings due to different prognostic characteristics depending on tumor location and resectability. Therefore, this study aimed to investigate the role of AC in distal cholangiocarcinoma (dCCA), a common tumor subtype of CCA. METHOD: Data from 497 patients with dCCA who underwent curative surgery at Seoul National University Hospital between 2000 and 2019 were reviewed using prospectively collected clinicopathologic information. RESULTS: The median overall survival (OS) and recurrence-free survival (RFS) in the entire cohort were 62.9 and 44.0 months, respectively. AC was associated with improved five-year OS (58.5% vs. 46.4%; p < 0.001) and RFS (49.9% vs. 40.7%; p = 0.005), particularly in patients with advanced T stages (≥ T3). Multivariate analysis revealed that AC was an independent positive prognostic factor for survival. Furthermore, adjuvant radiotherapy (RT) alone provides no survival benefit, whereas AC combined with RT (AC + RT) offers greater benefits, particularly for patients with positive resection margins. CONCLUSION: AC improved the postoperative survival outcomes of patients with dCCA who underwent curative surgery. Furthermore, AC + RT appears to provide greater benefits, especially for patients with positive resection margins.