移植技術と研究

Introduction: Primary liver cancer arises from hepatocytes or biliary epithelium resulting in hepatocellular carcinoma or cholangiocarcinoma, respectively. Mixed hepatocellular carcinoma-cholangiocarcinomas are rare; therefore, medical literature addressing these tumors is limited. As treatment modalities for mixed hepatocellular carcinoma-cholangiocarcinomas are few, the role of orthotopic liver transplantation remains controversial. Aim: To determine the survival outcomes of patients with incidentally discovered mixed hepatocellular carcinomacholangiocarcinomas after orthotopic liver transplantation. Methods and Materials: We present five patients with mixed hepatocellular carcinoma-cholangiocarcinomas who received orthotopic liver transplantation at our institution between September 1998 and July 2011. Characterization of the combined lesion was based on the Allen and Lisa classification scheme: type A: separate neoplasms of liver cell or bile duct cell; type B: different masses that mingle as they grow; and type C: masses that display both features of liver and bile duct cells. Results: Preoperatively, all patients met Milan criteria based on presumed hepatocellular carcinoma prior to orthotopic liver transplantation. Multifocal disease was present in all patients on pathological diagnosis, which was not appreciated during preoperative screening, and histologic characterization of the lesions revealed both Allen and Lisa types A (60%) and C (40%). All of our patients had underlying cirrhosis. The post-operative course was uneventful in all of the cases. Vascular invasion was observed in one patient who developed bone metastases and subsequently died 600 days post-transplant despite post-transplant chemoradiation therapy. The other four patients have remained disease-free; the mean overall survival is 800 days. Our population is unique in prevalence of cirrhosis and multiple hepatic lesions as compared to other case series. Conclusions: Although orthotopic liver transplantation is not recommended for patients with known mixed hepatocellular carcinoma-cholangiocarcinomas, in the event that a patient is transplanted, this case series shows that orthotopic liver transplantation is an acceptable treatment modality with appropriate survival outcomes.