Chronological analysis of surgical and oncological outcomes after the treatment of perihilar cholangiocarcinoma

BACKGROUNDS/AIMS: Despite advances in surgical techniques and perioperative supportive care, radical resection of hilar cholangiocarcinoma is the only modality that can achieve long-term survival. We chronologically investigated surgical and oncological outcomes of hilar cholangiocarcinoma and analyzed the factors affecting overall survival. METHODS: We retrospectively enrolled 165 patients with hilar cholangiocarcinoma who underwent liver resection with a curative intent. The patients were divided into groups based on the period when the surgery was performed: period I (2005-2011) and period II (2012-2018). The clinicopathological characteristics, perioperative outcomes, and survival outcomes were analyzed. RESULTS: The patients’ age, serum CA19-9 levels, and serum bilirubin levels at diagnosis were significantly higher in the period I group. There were no differences in pathological characteristics such as tumor stage, histopathologic status, and resection status. However, perioperative outcomes, such as estimated blood loss (1528.8 vs. 1034.1 mL, p=0.020) and postoperative severe complication rate (51.3% vs. 26.4%, p=0.022), were significantly lower in the period II group. Regression analysis demonstrated that period I (hazard ratio [HR]=1.591; 95% confidence interval [CI]=1.049-2.414; p=0.029), preoperative serum bilirubin at diagnosis (HR=1.585; 95% CI=1.058-2.374; p=0.026), and tumor stage (III, IV) (HR=1.671; 95% CI: 1.133-2.464; p=0.010) were significantly associated with poor prognosis. The 5-year survival rate was better in the period II patients than in the period I patients (35.1% vs. 21.0%, p=0.0071). CONCLUSIONS: The surgical and oncological outcomes were better in period II. Preoperative serum bilirubin and advanced tumor stage were associated with poor prognosis in patients with hilar cholangiocarcinoma.