Multi-Center Analysis of Liver Transplantation for Combined Hepatocellular Carcinoma-Cholangiocarcinoma Liver Tumors.

BACKGROUND: Combined hepatocellular-cholangiocarcinoma liver tumors (cHCC-CCA) with pathologic differentiation of both hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma within the same tumor are not traditionally considered for liver transplantation due to perceived poor outcomes. Published results are from small cohorts and single centers. Through a multicenter collaboration, we performed the largest analysis to date of the utility of liver transplantation for cHCC-CCA. STUDY DESIGN: Liver transplant and resection outcomes for HCC (n = 2,998) and cHCC-CCA (n = 208) were compared in a 12-center retrospective review (2009 to 2017). Pathology defined tumor type. Tumor burden was based on radiologic Milan criteria at time of diagnosis and applied to cHCC-CCA for uniform analysis. Kaplan-Meier survival curves and log-rank test were used to determine overall survival and disease-free survival. Cox regression was used for multivariate survival analysis. RESULTS: Liver transplantation for cHCC-CCA (n = 67) and HCC (n = 1,814) within Milan had no significant difference in overall survival (5-year cHCC-CCA 70.1%, HCC 73.4%, p = 0.806), despite higher cHCC-CCA recurrence rates (23.1% vs 11.5% 5 years, p < 0.001). Irrespective of tumor burden, cHCC-CCA tumor patient undergoing liver transplant had significantly superior overall survival (p = 0.047) and disease-free survival (p < 0.001) than those having resection. For cHCC-CCA within Milan, liver transplant was associated with improved disease-free survival over resection (70.3% vs 33.6% 5 years, p < 0.001). CONCLUSIONS: Regardless of tumor burden, outcomes after liver transplantation are superior to resection for patients with cHCC-CCA. Within Milan criteria, liver transplant for cHCC-CCA and HCC result in similar overall survival, justifying consideration of transplantation due to the higher chance of cure with liver transplantation in this traditionally excluded population.