Microwave Ablation as Bridging Therapy for Patients with Hepatocellular Carcinoma Awaiting Liver Transplant: A Single Center Experience

Purpose: To determine the pathologic response of computed tomography-guided percutaneous microwave ablation as bridging therapy for patients with hepatocellular carcinoma awaiting liver transplant, and its subsequent effect on survival. Materials and Methods: A single-center retrospective analysis was conducted on 62 patients (M:F = 50:12) with mean age of 59.6 years ± 7.2 months (SD). Sixty-four total MWA procedures were performed for hepatocellular carcinomas within Milan criteria as bridging therapy to subsequent orthotopic liver transplant between August 2014 and September 2018. The pathology reports of the explanted livers were reviewed to assess for residual disease. Residual disease was categorized as complete or incomplete necrosis. Patient demographics, tumor/procedural characteristics, and laboratory values were evaluated. Survival from time of ablation and time of transplantation were recorded and compared between cohorts using log rank tests. Results: The mean tumor size was 2.4 cm ± 0.7 cm (SD), (range = 1–4.6 cm). 32 (50%) cases required hydrodissection. Histopathologic necrosis was seen in 66% of cases at time of liver transplantation. Median time to liver transplant post-MWA was 12.6 months. [IQR = 8.6–14.8 months]. The median survival from ablation was 60.8 months [IQR = 45.5–73.7 months], and the median survival from transplant was 49.3 months [IQR = 33.7–60.1 months]. There was no significant difference in survival for patients with complete versus incomplete necrosis from ablation or liver transplant (p = 0.49, p = 0.46, respectively). Conclusions: Computed tomography-guided percutaneous microwave ablation is an effective bridge to orthotopic liver transplantation for patients with hepatocellular carcinoma. CEBM Level of Evidence: Level 3, non-randomized controlled cohort study/follow-up study.