Usefulness of the Kyoto criteria as expanded selection criteria for liver transplantation for hepatocellular carcinoma

Background. Previously, we proposed expanded selection criteria for liver transplantation (LT) for hepatocellular carcinoma (HCC), the Kyoto criteria, involving a combination of tumor number <= 10, maximal diameter of each tumor <= 5 cm, and serum des-gamma-carboxy prothrombin levels <= 400 mAU/mL, and we have used these criteria since January. 2007. In the present study, the usefulness of the criteria was validated prospectively as well as retrospectively. Methods. One hundred ninety-eight patients with HCC who underwent living donor LT (LDLT) from February 1999 through December 2011 were enrolled in this study. Overall survival and recurrence rates were investigated in patients classified according to the Kyoto criteria, the Milan criteria, or previous treatments for HCC. Tumor biological aggressiveness, including microvascular invasion and histologic differentiation, according to selection criteria was also examined. Results. The 5-year overall survival for patients within the Kyoto criteria (n = 147; 82%) was greater than that for the 49 patients exceeding them (n = 49; 42%; P < .001). The 5-year recurrence rate for patients within the Kyoto criteria (4.4%) was less than that for patients exceeding them (51%; P < .001). Intention-to-treat analysis of the 62 patients who underwent LDLT after implementation of the Kyoto criteria showed that the 5-year overall survival rate and the recurrence rate were 82% and 7%, respectively. Tumor biology was significantly less aggressive in patients within the Kyoto criteria. Conclusion. The Kyoto criteria are useful expanded criteria for LDLT for HCC and could help to achieve favorable outcomes.