neoplasm embryonal neoplasm embryonal tumour EMBT ONCOTREE:EMBT UMLS:C0027654 MONDO:0005564 MEDGEN:45034 EFO:0005784 embryonal tumor DOID:688 NCIT:C3264 A usually malignant neoplasm composed of primitive (immature) tissues that resemble fetal tissues. Medulloblastoma, Ependymoblastoma, Pineoblastoma, and Wilms tumor are representative embryonal neoplasms. --2003 embryonal neoplasm