Recurrence of hepatocellular carcinoma as a mixed hepatoblastoma after liver transplantation.

BACKGROUND Hepatoblastoma is an exceptional cause of primary malignant liver tumour in the adult. PATIENT The case is reported of an adult patient transplanted for alcoholic cirrhosis complicated by multifocal hepatocellular carcinoma in whom a recurrence in the form of a mixed hepatoblastoma invading the whole transplanted liver developed three months after liver transplantation. METHODS Complete clinical, histopathological, and immunohistochemical data were reviewed. RESULTS The recurrent tumour invaded the whole liver. The major component was a mixed hepatoblastoma, with an epithelial component expressing cytokeratin and a mesenchymal component expressing vimentin. The tumour also contained a minor hepatocarcinomatous component expressing alpha fetoprotein. The rapid growth of the tumour prevented any attempt at treatment. Although direct evidence is lacking, the most likely hypothesis to explain the observations is a marked phenotypic change in the initial malignant population at recurrence. CONCLUSION This case supports a possible filiation between hepatocellular carcinoma and hepatoblastoma in adults.