Differences in Prognostic Factors and Recurrence Patterns After Curative-Intent Resection of Perihilar and Distal Cholangiocarcinomas

Background: Perihilar cholangiocarcinoma and distal cholangiocarcinoma arise from the same tissue but require different surgical treatment methods. It remains unclear whether these cholangiocarcinoma types have different outcomes, prognostic factors, and/or recurrence patterns. Methods: This retrospective study evaluated patients who underwent curative-intent resection for perihilar cholangiocarcinoma or distal cholangiocarcinoma at a tertiary academic hospital during 2000-2015. Survival and prognostic factors were identified using Kaplan-Meier and Cox regression analyses. Results: The 90-day mortality rates were 0% for perihilar cholangiocarcinoma (36 patients) and 4% for distal cholangiocarcinoma (47 patients). There were no significant differences between perihilar cholangiocarcinoma or distal cholangiocarcinoma in median overall survival (30.9 vs 40.4 months) or median disease-free survival (14.2 vs 21.4 months). Among perihilar cholangiocarcinoma patients, age > 65 years was an independent predictor of poorer overall survival (hazard ratio: 2.45, 95% confidence interval: 1.07-5.64), while requiring bile duct re-resection was an independent predictor of disease-free survival (hazard ratio: 2.76, 95% confidence interval: 1.01-7.51). Among distal cholangiocarcinoma patients, a pN1 category independently predicted poorer overall survival (hazard ratio: 3.40, 95% confidence interval: 1.14-10.11), while preoperative CA19-9 levels >30 U/mL (hazard ratio: 2.51, 95% confidence interval: 1.09-5.79) and pN1 category (hazard ratio: 2.51, 95% confidence interval: 1.09-5.79) predicted a shorter disease-free survival. Local recurrence was more common with perihilar cholangiocarcinoma (50% of recurrences), while multiple synchronous sites were more common for distal cholangiocarcinoma (41% of recurrences). Conclusion: Perihilar cholangiocarcinoma and distal cholangiocarcinoma patients have similar survival outcomes. However, local control appears to be more prognostic for perihilar cholangiocarcinoma patients, while positive lymph nodes are critical prognostic factor for distal cholangiocarcinoma patients.