Toward a better liver graft allocation that accounts for candidates with and without hepatocellular carcinoma

In some countries where the Model for End-Stage Liver Disease (MELD) score is used for graft allocation, selected patients with hepatocellular carcinoma (HCC) receive a fixed number of exception points at listing, and increasing priority on the list by accruing additional exception points at regular time intervals. This system originally aimed at balancing the risks of HCC patients of developing contraindications and of non-HCC patients of dying before transplantation, is not ideal because it appears to offer an advantage to HCC patients, regardless of tumor characteristics and response to loco-regional treatment. Scores modulated by HCC characteristics have been proposed. They are based on a more refined estimate of the risk of pretransplant drop-out or of the posttransplant transplant benefit expressed as the life-years gained for each graft. This review describes the newly proposed systems, and discusses their advantages and drawbacks. We believe that the current exception points allocation should be revised and that drop-out-equivalent or transplant benefit-equivalent models should be studied further. As with all policy changes, these should be done under close monitoring that allows subsequent revisions.