Long-Term Outcomes of Combined Hepatocellular Carcinoma-Cholangiocarcinoma After Liver Transplantation in Patients with or without Concurrent Hepatocellular Carcinoma

BACKGROUND Combined hepatocellular carcinoma-cholangiocarcinoma (CHC), a rare disease, is usually an incidental diagnosis after liver transplantation (LT). In this study, we investigated the long-term post-transplant outcomes of CHC patients. MATERIAL AND METHODS From 2000 to 2022, 60 CHC patients were identified from a single-center database containing 6985 adult LT cases. RESULTS The incidence of CHC in adult LT patients was 0.9%. All CHC cases, except 1, were diagnosed incidentally in explanted livers. The mean CHC tumor diameter was 2.5±1.7 cm, and 51 recipients (85.0%) had a single tumor. Viable hepatocellular carcinoma (HCC) co-existed CHC in 23 patients (38.3%). The 5-year all-type tumor recurrence (TR) and overall survival (OS) rates were 37.9% and 57.7%, respectively. The presence of concurrent HCC did not affect all-type TR (p=0.228) or OS (p=0.083). The tumor stage of CHC was a significant prognostic factor for TR (p=0.017) and OS (p=0.038). In 37 patients with CHC alone, TR occurred in 13 (35.1%). In 23 patients with concurrent HCC, all-type TR occurred in 11 cases (47.8%). The 5-year TR and OS rates for 17 patients with very early-stage CHC without concurrent HCC were 17.6% and 82.4%, respectively. CONCLUSIONS CHC is a rare diagnosis following LT, and 38.3% of patients in this study had concurrent HCC. The post-transplant prognosis of CHC was unfavorable, except for patients with very early-stage CHC. Given that the majority of recurrences occur within the first 5 years after transplantation, intensive surveillance is crucial during this high-risk period. Patients with very early-stage CHC may be appropriate candidates for LT.