Locoregional therapy for hepatocellular carcinoma before transplant: Impact on tumor necrosis, tumor recurrence, and long-term survival.

Abstract

579 Background: To assess the effectiveness of different pre-transplant loco-regional therapy (LRT) approaches in patients with hepatocellular carcinoma (HCC) by tumor necrosis in liver explants, predictors of post-liver transplantation (LT) HCC recurrence and overall survival after LT. Methods: A retro analysis on consecutive patients who received LRT for HCC, within and beyond Milan criteria, prior to LT over a 12-year period. Categorical and continuous variables were examined using one-way ANOVA, while correlations among continuous variables were evaluated using correlation analysis. Linear regression was utilized to identify predictive factors. Survival outcomes were analyzed using the Kaplan-Meier method, with differences assessed via the log-rank test. Additionally, multivariate regression analysis was performed to explore the association between categorical and continuous variables and the risk of post-transplant recurrence. Results: 165 patients with HCC treated with 233 LRT sessions (median 1, range 1-5) prior to LT; 125 (76%) within Milan and 40 (24%) downstaged outside Milan, 30 (18%) had microvascular invasion in explants. Kaplan-Meier analysis showed median OS was 127 months post LT; mean 96 ± 4 months. The overall explant tumor necrosis after LT was 86%. The overall tumor necrosis with TACE+ablation, Y90, ablation, and TACE were 92, 89.3, 85.4 and 71%, respectively (p<0.05). The recurrence-free survival rates for patients treated with TACE+ablation and Y90 were both ≥90% (p=0.038) in comparison with ablation and TACE alone. Recurrence of HCC occurred in 12 patients (7.2%) over median follow-up of 11.5 months (range 4-52). Mean OS was 103 months (SD: 4, 95% CI: 95–111) for Milan In, and 92 months (SD: 9, 95% CI: 73–110) for Milan Out. Within Milan with bridging LRTs, 5 out of 125 (4%) experienced recurrence, while outside of Milan with downstaging LRTs, 7 out of 40 patients (18%) developed recurrences. Outside of Milan down-staged, pre-LRT AFP and microvascular invasion in explants were significantly and independently associated with recurrence (p=0.04, p=0.004 and p=0.02). Conclusions: The bridging and downstaging LRTs resulted in overall pathologic tumor necrosis of 86% (P>0.05). Median OS was 127 months; mean 96 ± 4 months. Mean OS was 103 months (SD: 4, 95% CI: 95–111) for Milan In, and 92 months (SD: 9, 95% CI: 73–110) for Milan Out. Post-LT recurrence-free survival in patients treated with TACE+ablation and Y90 was ≥90% (p<0.05). These findings highlight the critical impact of effective pre-transplant loco-regional therapy on long-term survival in HCC patients. Outside of Milan down-staged, pre-transplant AFP, and microvascular invasion in explants were significantly and independently correlated with post-LT HCC recurrence.