BACKGROUND
Complete pathological response (CPR) after locoregional treatments (LRTs) predicts better outcomes in patients with hepatocellular carcinoma (HCC) after living donor liver transplantation (LDLT). This study aimed to find risk factors associated with HCC recurrence in patients with LRT-induced CPR of HCC.
MATERIAL AND METHODS
Prognostic factors were identified from a development cohort of 313 patients from a high-volume single-center LDLT database and validated using a nationwide cohort of 418 patients from the Korean multi-center transplantation registry.
RESULTS
In the development study, 380 LRT sessions were performed on 313 patients, while the validation study included 482 sessions for 418 patients. Cumulative tumor recurrence and overall survival rates in the development study showed recurrence rates of 2.0%, 3.9%, 3.9%, and 4.5% and overall survival rates of 97.1%, 93.5%, 91.4%, and 89.2% at 1, 3, 5, and 10 years, respectively, respectively. In the validation study, tumor recurrence rates were 3.4%, 5.6%, and 7.7%, and overall survival rates were 98.6%, 96.0%, and 93.5% at 1, 3, and 5 years, respectively. Multiplicity of non-viable tumors was identified as a significant risk factor for tumor recurrence (P=0.001; HR=9.83) and overall survival (P=0.021; HR=2.91) in the development study, whereas the composite AFP–PIVKA-II score did not show significance. The validation study confirmed that the multiplicity of non-viable tumors was the only significant risk factor for tumor recurrence (P=0.026; HR=2.47) and overall survival (P=0.017; HR=2.82).
CONCLUSIONS
This study demonstrates that LDLT recipients exhibiting LRT-induced CPR with multiple non-viable tumors constitute a high-risk subgroup and may require intensive posttransplant surveillance.

Keywords: Carcinoma, Hepatocellular; Necrosis; Recurrence; Response Evaluation Criteria in Solid Tumors; Transplantation