Concurrent infantile hemangioendothelioma and mesenchymal hamartoma in a developmentally arrested liver of an infant requiring hepatic transplantation.

A newborn female underwent a surgical resection for a hepatic mass discovered prenatally by ultrasonography, and diagnosed pathologically as a mesenchymal hamartoma. Within 4 months after surgery, multiple cutaneous hemangiomas developed and a multinodular mass was detected in the liver. A liver biopsy showed an infantile hemangioendothelioma with type I features. An orthotopic liver transplant was performed due to the extensive nature of the hepatic involvement and progressive respiratory compromise. Virtually the entire liver was involved by a large infantile hemangioendothelioma. A multicystic mesenchymal hamartoma was also found on the left side. In addition, the uninvolved hepatic parenchyma had features recapitulating the fetal liver. This simultaneous involvement of the liver by a mesenchymal hamartoma and infantile hemangioendothelioma is unique. A review of the literature revealed only one incompletely characterized case with similar findings.