Primary Hepatic Tumors in Infancy and Childhood

Personal observations of representative hepatic tumors—adenoma, hepatoblastoma (embryonal and fetal types), trabecular hepatocarcinoma, infantile hemangioendothelioma, and teratoma—are reported. The tumors are reviewed on the basis of a new proposed classification, including the main groups of epithelial, mesenchymal, and teratomatous forms. Benign epithelial tumors are represented by adenomas (hepatocellular and cholangiocellular) and by the controversial adrenal rest tumors. Malignant epithelial tumors, the group best known, include hepatoblastomas (anaplastic, embryonal, fetal, and mixed) and trabecular hepatocarcinomas. The immunochemical diagnostic test for serum alpha1 fetoprotein recently has been applied to patients with these tumors. The benign mesenchymal tumors are mainly represented by infantile hemangioendothelioma, cavernous hemangioma, lymphangioma (cavernous and cystic), and the so-called mesenchymal hamartoma. The malignant mesenchymal tumors include myoblastic sarcoma, mesenchymoma, fibrosarcoma, and angiosarcoma. Histogenetic features of hepatoblastomas are discussed on the basis of biologic and clinical data.