Endodermal sinus tumor is characterized by

Yolk sac tumors/Schiller-Duval body are the most common primary testicular neoplasm in children younger than 3 years of age; in this age group it has a very good prognosis. In adults, yolk sac tumors most often are seen admixed with embryonal carcinoma.A distinctive feature is the presence of structures resembling primitive glomeruli, the so-called Schiller Duvall bodies. ref : Robbins Basic Pathology, 9E,page-661 Ref of img