Congenital hepatic mesenchymal hamartoma associated with mesenchymal stem villous hyperplasia of the placenta: case report.

A newborn with an unusual association of hepatic mesenchymal hamartoma and mesenchymal stem villous hyperplasia of the placenta is presented. At birth, the large hepatic mass caused severe respiratory distress necessitating early surgical intervention. This report on the association of hepatic mesenchymal hamartoma and mesenchymal stem villous hyperplasia of the placenta strongly suggests a common pathogenetic origin of the 2 lesions.