the embryonal carcinoma cell is the totipotential stem cell that resembles normal germ cells in many ways and is capable of differentiating along the somatic pathways to form endoderm , mesoderm and ectoderm cell types ( teratoma ) or along extraembryonic pathways to form trophoblast ( choriocarcinoma ) or yolk sac ( endodermal sinus tumor ) .
C0017471
germ cells
C0039538
teratoma