Liver Transplantation Following Yttrium-90 Radioembolization: 15-year Experience in 207-Patient Cohort

Radioembolization (Y90) is used in hepatocellular carcinoma (HCC) as a bridging as well as downstaging liver directed therapy to curative liver transplantation. In this study we report long-term outcomes of liver transplantation (LT) for HCC patients bridged/downstaged by Y90. Patients undergoing LT following Y90 between 2004-2018 were included, with staging by United Network of Organ Sharing (UNOS) TNM at baseline pre-Y90 and pre-LT. Post-Y90 toxicities were recorded. Histopathological data of HCC at explant were recorded. Long-term outcomes including overall survival (OS), recurrence-free survival (RFS), disease-specific mortality (DSM) and time-to-recurrence (TTR) were reported. Time-to-endpoint analyses were estimated using Kaplan-Meier. Uni/multivariate analyses were performed using log-rank test and Cox proportional hazards model, respectively. During the 15-year period, 207 patients underwent LT after Y90. OS from LT was 12.5 years, with median time to LT of 7.5 months (IQR: 4.4-10.3). 169 patients were bridged while 38 were downstaged to LT. 94 (45%), 60 (29%) and 53 (26%) patients showed complete, extensive and partial tumor necrosis on histopathology. Three, five and ten-year OS rates were 84%, 77%, and 60% respectively. Twenty-four patients developed recurrence, with median RFS of 120 (95%CI: 69-150) months. DSM at 3, 5 and 10 years was 6%, 11% and 16% respectively. There were no differences in OS/RFS for bridged or downstaged patients. RFS was higher in patients with complete/extensive versus partial tumor necrosis (p<0.0001). For UNOS T2 patients treated during the study period, 5.2% dropped out due disease progression. Conclusion: Y90 is an effective treatment for HCC in the setting of bridging/downstaging to LT. Patients who achieved extensive or complete necrosis had better RFS, supporting the practice of neoadjuvant treatment prior to LT.