Endodermal sinus (yolk sac) tumors in infants and children.

Endodermal sinus tumors, as a specific entity, were first proposed and described by Teilum on the basis of morphological and histogenetic features. Recent work utilizing tumor markers (alpha-fetoprotein), immunofluorescent and electron microscopic studies have supported Teilum's original concept as to the origin of these tumors. Five typical presentations of endodermal sinus tumors seen in the pediatric age group were reviewed with reference to the original presentation, the utilization of tumor markers (alpha-fetoprotein) and the prognostic implications of this neoplasm.