Striving for decreased post-transplant hepatocellular carcinoma recurrence without excluding potentially curable patients: the utility of tumor biology
The Milan criteria truly transformed the field of transplantation for hepatocellular carcinoma by demonstrating that excellent recurrence-free survival (RFS) can be achieved in small tumors (1). Over the years, the allowable tumor size and number prior to transplantation was challenged by several groups and thus continued to expand, but the use of simple morpho-metrics always limited the ability to predict tumor recurrence, as markers of tumor biology were not routinely used. More recently, multiple studies have combined biomarkers with tumor size and number to create increasingly accurate scoring systems to better predict RFS. The adoption of the AFP model in France (2), accounting for log AFP and tumor size and number, in addition to the newest model by Mazzaferro et al., Metroticket 2.0 (3), a more fluid model utilizing similar criteria to the AFP model, join the MORAL score (4), which incorporates the neutrophil lymphocyte ratio (NLR), and the NYCA score (5), which incorporates AFP response, as the best current predictors of RFS available to date.