Long-Term Prognostic Significance of TACE-Induced Complete Pathological Response in Patients with Hepatocellular Carcinoma Who Have Undergone Liver Transplantation

BACKGROUND Complete pathological response (CPR) after transcatheter arterial chemoembolization (TACE) is associated with improved posttransplant outcomes in patients with hepatocellular carcinoma (HCC). This study evaluated the prognostic significance of TACE-induced CPR in patients with HCC who underwent liver transplantation (LT). MATERIAL AND METHODS The records of 2238 patients who underwent primary LT for HCC between January 2006 and December 2020 were retrospectively reviewed; of these, 253 achieved explant pathology-confirmed TACE-induced CPR. Their clinical outcomes were analyzed. RESULTS These 253 patients underwent an average of 2.2±2.3 TACE sessions. The median number of non-viable tumors was 1, and the median maximal tumor size was 1.6 cm. At 1, 3, 5, 10, and 15 years, cumulative post-LT recurrence rates were 1.2%, 3.3%, 3.3%, 5.6%, and 5.6%, respectively; overall patient survival rates were 96.0%, 93.7%, 92.4%, 91.3%, and 82.1%, respectively. Larger tumors (>2 cm) and multiple non-viable tumors were independently associated with higher recurrence and reduced survival rates (P≤0.036). Cluster analysis identified patients with multiple non-viable tumors larger than 2 cm as a high-risk group; others comprised a low-risk group. Recurrence (P<0.001) and survival (P=0.018) rates were significantly lower in the high-risk group than in the low-risk group. CONCLUSIONS TACE-induced CPR is a strong prognostic indicator of favorable long-term outcomes after LT in patients with HCC. Stratification based on non-viable tumor size and number can identify high-risk patients with CPR who require closer surveillance. Less intensive follow-up may be sufficient for low-risk patients.