malignant teratoma extragonadal nonseminomatous germ cell tumor immature teratoma immature extragonadal teratoma MEDGEN:167781 extragonadal primary malignant teratoma primary malignant extragonadal teratoma malignant extragonadal teratoma GARD:0025465 MONDO:0024857 An immature teratoma that develops as a primary tumor in an anatomic site other than the testis or ovary. UMLS:C0855163 NCIT:C8884 immature extragonadal teratoma