Comparison of models for tumor recurrence after liver transplantation for the patients with hepatocellular carcinoma: A multicenter long-term follow-up study

Abstract

BACKGROUND AND AIMS: Several models have been developed to predict tumor the recurrence of hepatocellular carcinoma (HCC) after liver transplantation besides the conventional Milan criteria (MC), including the MoRAL score. This study aimed to compare the prognostication power of the MoRAL score to most models designed so far in the Eastern and Western countries.  METHODS: This study included 564 patients who underwent living donor liver transplantation (LDLT) in three large-volume hospitals in Korea. The primary and secondary endpoints were time-to-recurrence, and overall survival (OS), respectively. The performance of the MoRAL score was compared with those of other various Liver transplantation (LT) criteria, including the Milan criteria, University of California San Francisco (UCSF) criteria, up-to-seven criteria, Kyoto criteria, AFP model, total tumor volume/AFP criteria, Metroticket 2.0 model, and Weill Cornell Medical College group model.  RESULTS: The median follow-up duration was 78.1 months. Among all models assessed, the MoRAL score showed the best discrimination function for predicting the risk of tumor recurrence after LT, with c-index of 0.78, compared to other models (all p < 0.001). The MoRAL score also represented the best calibration function by Hosmer-Lemeshow test (p = 0.15). Especially in the beyond-MC sub-cohort, the MoRAL score predicted tumor recurrence (c-index, 0.80) and overall survival (OS) (c-index, 0.70) significantly better than any other models (all p < 0.001). When the MoRAL score was low (<314.8), the five-year cumulative risks of tumor recurrence and death were excellent in beyond-MC (27.8%, and 20.5%, respectively) and within-MC (16.3%, and 21.1%, respectively) sub-cohorts.  CONCLUSIONS: The MoRAL score provides the most refined prognostication for predicting HCC recurrence after LDLT.