Richard B. Freeman, Robin Ruthazer, Anthony Schore, Abigail Mithofer, Khanh Ngyuen, Prakhar Agarwal, Ann Harper, Erick B. Edwards. Division of Transplantation, Department of Surgery, Tufts-New England Medical Center, Boston, MA, USA; Division of Gastroenterology/Hepatology, Massachusetts General Hospital, Boston, MA, USA; Research, United Network for Organ Sharing, Richmond, VA, USA

　　Loco-regional ablative therapy (AT) for HCC has been used to limit liver transplant (LT) waiting list drop out rates but has not been examined for down-staging efficacy and post transplant outcomes. We compared histology and post transplant survival results for 552 patients with AT with 736 patients with no AT who were registered with HCC priority on the US LT list. Of the AT group, 292 (52.9%) had TACE, 189 (34.2%) had RFA and 71 (12.9%) had other or multiple ATs a mean of 174 days before transplant with AT types distributed evenly among listing stages and time from treatment to transplant. On histologic examination significantly more patients who received AT had a histologic stage (HS) less advanced than their most recent listing stage (LS) compared with those who did not have AT (P< 0.0001) indicating a significant down-staging effect of AT. Patients treated with TACE were more likely to have down staged tumors (P=0.0202) compared with those treated with RFA. Completely necrotic nodules were more frequently reported with TACE (36.3%) compared with RFA (31.6%), (P=0.0409) but both AT types had no necrosis on 19.9% and 19.5% of cases respectively. We observed a trend toward better 2 year K-M survival after LT for the AT vs no AT group (81% vs 76%, P=0.121) with no difference in survival among AT types (P=0.7853). Patients with AT who had partial or complete responses achieved better 2-year survival compared with no AT 81% vs 71%, P=0.013). We conclude that AT (TACE>RFA) appears to down-stage HCC and that there may be a survival benefit for AT treated patients, especially those with documented necrotic responses, after liver transplantation.