Variations in liver allocation systems across continents with a focus on MELD exceptions

Variations in liver allocation systems worldwide are presented, with a specific focus on regional differences and their potential impact on outcomes, with the goal of serving as a reference for future policy development. Summaries of liver allocation across multiple European, Scandinavian, and Asian systems, as well as the combined allocation system of Australia plus Canada, the United States, and the systems in Central America, South America, and the Caribbean are reviewed. A comprehensive comparison of how different regions address MELD exceptions, primarily focusing on hepatocellular carcinoma, along with the most common etiologies of liver disease requiring transplantation is presented. In addition, the adoption of living donation and donation after circulatory death is discussed. The study involves contributions from a diverse group of world experts in liver transplantation and may serve as an essential resource to foster international dialogue as countries strive to optimize organ allocation policies, including MELD exceptions.