obsolete_Testicular Yolk Sac Tumor true ONCOTREE:TYST UMLS:C0279708 testicular endodermal sinus neoplasm yolk Sac neoplasm of testis yolk Sac neoplasm of the testis GARD:0000348 yolk Sac tumor of testis Orchidoblastoma endodermal sinus tumor of the testis endodermal sinus neoplasm of the testis yolk sac tumor yolk Sac tumor of the testis testis yolk sac tumor http://purl.obolibrary.org/obo/MONDO_0003402 endodermal-sinus tumor endodermal sinus tumor of testis testicular yolk sac tumor testicular yolk Sac neoplasm testicular endodermal sinus tumor EFO:1000574 3.88.0 endodermal sinus neoplasm of testis Replaced by Mondo term MONDO_0003402, with which this term was previously merged. Use: http://purl.obolibrary.org/obo/MONDO_0003402 DOID:5344 NCIT:C8000 A non-seminomatous malignant germ cell tumor arising from the testis. It affects infants, young children, and postpubertal males. It is the most frequently seen testicular neoplasm during childhood. The vast majority of patients present with an asymptomatic scrotal mass. The tumor mimics the yolk sac of the embryo and produces alpha-fetoprotein (AFP). It metastasizes to distant anatomic sites. Prognostic factors relate to the clinical stage and the degree of AFP elevation.