Classification of primary malignant tumors of liver in infancy and childhood.

Abstract

The clinical records and pathologic material of 24 cases of primary malignant tumors of liver in infancy and childhood are reviewed. The authors demonstrate that such tumors can be classified into two groups: (1) occurring in infants and children to three years of age and characterized by a mixture of embryonal hepatic parenchymal tissue and neoplastic mesenchymal tissue; (2) occurring in children older than 6 years and characterized by hepatic parenchymal elements alone. The tissues from three patients in the younger age group and two patients in the older age group were studied with the electron microscope. The tumor cells of the younger age group demonstrate a few cytoplasmic organelles indicating their embryonal nature. The tumor cells of the older age group demonstrate a large number of mitochondria and irregularly arranged endoplasmic reticulum. The authors conclude that tumors of the younger age group are embryonal and congenital in origin. Tumors of the older age group are clinically and histologically similar to the hepatomas in the adult although further investigation is needed to determine the nature of these tumors.