Current controversies surrounding liver transplantation for hepatocellular carcinoma.

Liver transplantation (LT) for hepatocellular carcinoma (HCC) has progressed rapidly over the last decade from a futile therapy to the first choice therapy for suitable patients. Excellent outcomes of LT for HCC can be largely attributed to the use of the Milan Criteria, which have restricted LT to patients with early stage tumors. These criteria may be conservative, and it is likely that a subset of patients with tumors beyond these criteria can have acceptable outcomes. However, there is currently insufficient data to accept more liberal criteria as a standard of care, and a higher quality evidence base must be achieved to prevent poor utilization of valuable donor liver resources. In the future, it is probable that more sophisticated selection criteria will emerge incorporating aspects of tumor biology beyond tumor size and number. Dropout from the waiting list due to tumor progression remains a clinical challenge particularly in regions with prolonged waiting times. Priority allocation using HCC MELD points is a practical and transparent solution that has successfully reduced waitlist dropout for HCC patients. Further refinements of the HCC MELD point system are required to ensure equity of access to LT for non-HCC patients and prioritization of HCC patients with the highest risk of dropout. Improving the evidence base for pre-LT locoregional therapy to prevent waitlist dropout is an urgent and difficult challenge for the LT community. In the interim transplant clinicians must restrict the use of these therapies to those patients who are most likely to benefit from them.