Surgical outcomes and prognostic factors of distal common bile duct adenocarcinoma: chronological analysis in a single high-volume institutional experience

BACKGROUND: Distal common bile duct (dCBD) cancer is typical indication for pancreaticoduodenectomy (PD). We aimed to retrospectively evaluate surgical outcomes and investigate prognostic factors of dCBD adenocarcinoma for which PD was performed at a single institution. METHODS: We searched consecutive cases of dCBD adenocarcinoma undergone PD at Samsung Medical Center from 1995 to 2018. Cases with distant metastasis or palliative intent were excluded. The year in which the survival rate was dramatically improved was identified and entire years were divided into two periods for comparison. To balance between the two periods, we conducted propensity score matching (PSM) analysis using age, sex, body mass index (BMI), and American Society of Anesthesiologist score. RESULTS: Total of 804 cases were enrolled in this study. The entire period was divided into early period of 18 years and recent period of 6 years. The early and late period included 466 and 338 patients, respectively. As a result of PSM, balanced 316 patients were selected from each of the two periods. Significant improvements in surgical outcomes were identified, including shorter operation time, fewer blood loss, shorter hospitalization, and favorable overall survival. As results of multivariable analysis of independent risk factors for overall survival, older age and advanced N stage were identified, as expected. It was distinct that aggressive surgery and advanced tumor state in the early period and a lower BMI in the late period negatively affected the survival, respectively. CONCLUSIONS: Surgical outcomes of dCBD cancer underwent PD was improved. There were few modifiable factors to improve survival and continuous further study is needed to detect dCBD cancer in the early stages.