Poorly differentiated hepatocellular carcinoma: resection is equivalent to transplantation in patients with low liver fibrosis

Abstract

Presenter: Omid Salehi MD | Saint Elizabeth's Medical Center Background: Organ allocation criteria for liver transplantation (e.g. Milan) focus on tumor size and multifocality to determine candidacy, while tumor differentiation and degree of liver damage are omitted. This study investigates a synergistic effect of hepatocellular carcinoma (HCC) differentiation grade with degree of liver fibrosis on survival when comparatively analyzing resection (SX) vs transplantation (LT) and whether these parameters should be included in organ allocation algorithms. Methods: The National Cancer Database was queried between 2004-2016 for patients with solitary HCC meeting Milan criteria undergoing SX vs. LT. Two groups were created based on liver damage (low fibrosis (LF) vs high fibrosis (HF)) and stratified by grade. Cox multivariable regression models, Kaplan-Meier survival analyses and log-rank tests were performed. Results: 1515 patients met inclusion criteria; 780 had LT and 735 had SX. Median overall survival (mOS) was 39.7 months and 5-year survival (5YS) was 58.2%; LT mOS was 47.9 months vs SX mOS of 34.9 months (P < .001), LT 5YS was 68.7% vs SX 5YS of 44.2% (P < .001). Multivariate analysis revealed SX, no chemotherapy, longer hospital length of stay, and age to be factors associated with worse survival. However, while transplantation conferred survival benefit for well-moderately differentiated tumors, type of surgery did not impact survival for poorly differentiated HCC in LF patients. This pattern was independent of tumor size. Conclusion: HCC differentiation and liver fibrosis, but not size, synergistically determine efficacy of SX vs. LT. Therefore, to optimally allocate organs for HCC transplantation, current criteria should give more weight to tumor grade or liver fibrosis compared to tumor size.