Source:http://linkedlifedata.com/resource/umls/id/C1333377
NCI: A malignant germ cell tumor of the central nervous system composed of large cells that proliferate in cohesive nests and sheets. In rare occasions, tumor cells may replicate the structure of the early embryo, forming "embryoid bodies" replete with germ discs and miniature amniotic cavities. Additional morphologic characteristics include enlarged nucleoli, abundant clear to somewhat violet-hued cytoplasm, a high mitotic rate and zones of coagulative necrosis. (Adapted from WHO)