Long term results of down-staging and liver transplantation for patients with hepatocellular carcinoma beyond the conventional criteria

The objective of the study is to evaluate 10 years of down-staging strategy for liver transplantation (LT) with a median follow-up of 5 years. Data on long-term results are poor and less information is available for hepatocellular carcinoma (HCC) non-responder patients or those ineligible for down-staging. The outcome of 308 HCC candidates and the long-term results of 231 LTs for HCC performed between 2003 and 2013 were analyzed. HCCs were divided according to tumor stage and response to therapy: 145 patients were T2 (metering Milan Criteria, MC), 43 were T3 successfully down-staged to T2 (Down-Achieved), 20 were T3 not fully down-staged to T2 (Down-not Achieved), and 23 patients were T3 not receiving down-staging treatments (No-Down). The average treatment effect (ATE) of LT for T3 tumors was estimated using the outcome of 535 T3 patients undergoing non-LT therapies, using inverse probability weighting regression adjustment. The 24-month drop-out rate during waiting time was significantly higher in the down-staging groups: 27.6% vs. 9.2%, p < 0.005. After LT, the tumor recurrence rate was significantly different: MC 7.6%, Down-Achieved 20.9%, Down-not Achieved 31.6%, and No-Down 30.4% (p < 0.001). The survival rates at 5 years were: 63% in Down-Achieved, 62% in Down-not Achieved, 63% in No-Down, and 77% in MC (p = n.s.). The only variable related to a better outcome was the effective down-staging to T2 at the histological evaluation of the explanted liver: recurrence rate = 7.8% vs. 26% (p < 0.001) and 5-year patient survival = 76% vs. 67% (p < 0.05). The ATE estimation showed that the mean survival of T3-LT candidates was significantly better than that of T3 patients ineligible for LT [83.3 vs 39.2 months (+44.6 months); p < 0.001]. Long term outcome of T3 down-staged candidates was poorer than that of MC candidates, particularly for cases not achieving down-staging. However, their survival outcome was significantly better than that achieved with non-transplant therapies.