For patients who are initially being listed for liver transplantation and for patients who are seeking to retain their active status on the wait list, the first step in the diagnostic consideration of hepatocellular carcinoma (HCC) is the accurate identification and staging of the tumors. Advances in imaging and biomarkers have improved our ability to diagnose HCC and in parallel have reduced the incidence of incidental HCC after liver transplantation. For the initial diagnosis, high sensitivity and high specificity are paramount considerations. The requirements change, however, when we are considering listing for transplantation: then, the prediction of the risk for posttransplant tumor recurrence and patient survival assume primacy. We must understand with confidence not only that the patient has a tumor but also that the tumor will affect the 5-year patient survival rate through the risk of tumor recurrence.
Our first task in making the decision to list a patient with HCC for liver transplantation is to rule out factors representing absolute contraindications: extrahepatic disease and macrovascular tumor inva-sion. Beyond these variables, an understanding of the risk of posttransplant HCC recurrence is dominated by 2 major variables: tumor mass and tumor biology. Three major types of information can inform the decision to list a patient with HCC for liver transplantation. The first and usually dominant factors are the imaging characteristics, which include the size and number of the malignant lesions. The second type consists of biomarkers, which are most commonly abnormal proteins in the circulation that signify the presence of more dedifferentiated malignant cells with a higher propensity to invade and metastasize. The third type consists of factors from histological evaluations of tumor tissue obtained by biopsy or excision; these include factors such as the tumor grade, the presence of microvascular invasion, and protein, messenger RNA (mRNA), or DNA markers that have been correlated with more aggressive tumor behavior.
Our team was tasked with generating recommendations for the best protocol for monitoring HCC patients on the wait list and for screening them for tumor recurrence after transplantation. The role of