How long should follow-up be continued after R0 resection of perihilar cholangiocarcinoma?

Background: Although several studies have been conducted on the patterns of recurrence in resected perihilar cholangiocarcinoma, the appropriate follow-up period after resection is still controversial. Methods: Consecutive patients who underwent an R0 resection of perihilar cholangiocarcinoma between 2001 and 2014 were reviewed retrospectively, focusing on the time and site of initial recurrence. A Cox proportional hazards model was used for multivariate analysis. Results: During the study period, 404 patients underwent R0 resection, of whom 242 patients (59.9%) developed a recurrence. The most common site of recurrence was locoregional, followed by peritoneum and liver. Approximately 70% of patients were asymptomatic when recurrence was detected. The median survival time in all cohorts was 4.8 years, and the estimated cumulative probability of recurrence was 54.3% at 5 years and 65.7% at 10 years. Multivariate analyses revealed that lymph node metastasis (hazard ratio 2.80, P < .001) and microscopic venous invasion (hazard ratio, 1.70, P < .001) were independent risk factors for recurrence-free survival. The cumulative probability of recurrence in 84 patients with 2 risk factors was nearly 90% at 5 years; even in the 178 patients without risk factors, the probability at 5 years was 30%, and thereafter, the probability of recurrence gradually increased, reaching nearly 50% at 10 years. No trends in the time and site of recurrence were detected. Conclusion: Approximately 60% of patients with perihilar cholangiocarcinoma experience recurrence after R0 resection. Even in patients without an independent risk for recurrence, the recurrence probability is high, reaching nearly 50% at 10 years. Thus, close surveillance for 10 years is necessary even after R0 resection of perihilar cholangiocarcinoma. (c) 2020 Elsevier Inc. All rights reserved.