Difference in tumor invasiveness in cirrhotic patients with hepatocellular carcinoma fulfilling the Milan criteria treated by resection and transplantation: impact on long-term survival.

SUMMARY BACKGROUND DATA Some previous studies demonstrated better survival after transplantation for small hepatocellular carcinoma (HCC) compared with resection, but the influence of differences in tumor invasiveness between transplanted and resected patients has not been studied. This study compared the tumor characteristics of patients with HCC within the Milan criteria treated by resection or transplantation, and elucidated their impact on long-term survival. PATIENTS AND METHODS Tumor characteristics and long-term survival of 204 cirrhotic patients with resection and 43 cirrhotic patients with transplantation for HCC within the Milan criteria were compared. A multivariate analysis was performed to determine the prognostic factors of survival in all patients with resection or transplantation. RESULTS Tumors in the transplanted group were associated with lower incidence of high-grade tumors, microscopic venous invasion, and microsatellite nodules. The overall 5-year survival was better in the transplantation group than the resection group (81% vs. 68%, P = 0.017). However, there were no significant differences in survival between the two groups when stratified according to presence or absence of venous invasion. Multivariate analysis showed that hepatitis C virus serology, tumor size, tumor number, and microscopic venous invasion, but not resection or transplantation, were of prognostic significance. CONCLUSIONS There were significant differences in tumor invasiveness in HCC treated by transplantation and resection as a result of selection bias, even in patients with the tumors fulfilling the Milan criteria. When the different tumor invasiveness was taken into account, there was no significant difference in the long-term survival after resection or transplantation.