Mesenchymal hamartoma of the liver of an infant--case report.

A 10-month-old boy was found to have a huge hepatic mesenchymal hamartoma. Histologically the lesion appeared as large islands of loose mesenchymal tissue with profuse cystic bile ducts and hepatic cells. There were profuse bile duct and blood-vessel communications between the hamartoma and the right lobe of the liver. Because of benign nature of this rare neoplasm, more conservative operations are indicated rather than formal hepatic lobectomy.