Impact of Radiation Therapy on Biliary Complications in Liver Transplantation Recipients with Hepatocellular Carcinoma: A Propensity Score-Matched Analysis

Background: The role of radiation therapy (RT) in managing hepatocellular carcinoma (HCC) patients has significantly expanded. Therefore, the use of radiation therapy for pre-transplantation has also increased these days. However, its impact on post-transplant outcomes, particularly biliary complications, is not well defined. This study aims to evaluate the effect of RT on biliary complications in LT(Liver transplantation) recipients with HCC, utilizing propensity score-matching method for analysis.
Methods: A retrospective study was conducted on 1,008 HCC patients underwent LT between January 2018 and December 2023. Patients were classified into RT and non-RT groups. Propensity score matching was performed to ensure comparability. Baseline characteristics were analyzed for both unmatched and matched cohorts. As the primary outcome, biliary complications were assessed. Logistic regression method was employed to analyze risk factors.
Results: RT was associated with an increased risk of biliary complications in both unmatched and matched analyses, particularly in biliary stricture(p= 0.005).

Logistic regression analysis identified RT as an independent risk factor for biliary complications, with the unmatched cohort showing an OR of 1.642 (p = 0.033) and the matched cohort demonstrating an OR of 1.960 (p = 0.015). Other factors like separated multiple bile duct anastomosis (p = 0.019) and dual LDLT(Living donor liver transplantation) (p = 0.004) are also significant risk factor of bile duct complication.
Conclusions: RT in LT recipients with HCC is associated with a higher risk of biliary complications. Also, separated multiple bile duct anastomosis and dual LDLT can affect post-transplantation outcome. Future prospective studies are necessary to optimize RT protocols and improve outcomes in this population.