Endodermal sinus tumor overview


 * Somal Khan, M.D.

Overview
Endodermal sinus tumor (EST), also known as yolk sac tumor (YST), is a member of the germ cell tumor group of cancers. Endodermal sinus tumor frequently develops within other kinds of germ cell tumor, particularly within teratoma. While pure teratoma is usually benign, endodermal sinus tumor is malignant.