BACKGROUNDPatients with combined hepatocellular carcinoma and cholangiocarcinoma (cHCC-CC) are not traditionally considered eligible for liver transplantation (LT) due to poor outcomes.AIMTo compare outcomes between living donor LT (LDLT) patients with hepatocellular carcinoma (HCC) and LT patients with cHCC-CC and to identify risk factors for tumor recurrence and death after LT in cHCC-CC patients.METHODSData for pathologically diagnosed cHCC-CC patients (n = 111) who underwent LT from 2000 to 2018 were collected for a nine-center retrospective review. Patients (n = 141) who received LDLT for HCC at Samsung Medical Center from January 2013 to March 2017 were selected as the control group. Seventy patients in two groups, respectively, were selected by 1:1 matching.RESULTSCumulative disease-free survival (DFS) and overall survival (OS) in the cHCC-CC group were significantly worse than in the HCC group both before and after matching. Extrahepatic recurrence incidence in the cHCC-CC group was higher than that in the HCC group (75.5% vs 33.3%, P < 0.001). Multivariate analysis demonstrated that the cHCC-CC group had significantly higher rates of tumor recurrence and death compared to the HCC group. In cHCC-CC subgroup analysis, frequency of locoregional therapies > 3, tumor size > 3 cm, and lymph node metastasis were predisposing factors for tumor recurrence in multivariate analysis. Only a maximum tumor size > 3 cm was a predisposing factor for death.CONCLUSIONThe poor prognosis of patients diagnosed with cHCC-CC after LT can be predicted based on the explanted liver. Frequent regular surveillance for cHCC-CC patients should be required for early detection of tumor recurrence.