Yolk Sac Tumor

**Semantic type:** Neoplastic Process

**Definition:** A non-seminomatous malignant germ cell tumor composed of primitive germ cells. It is the most common malignant germ cell tumor in the pediatric population. It occurs in the infant testis, ovary, sacrococcygeal region, vagina, uterus, prostate, abdomen, liver, retroperitoneum, thorax, and pineal/third ventricle. The tumor mimics the yolk sac of the embryo and produces alpha-fetoprotein (AFP). Treatment includes: surgical resection, radiation, and chemotherapy. This tumor is very responsive to chemotherapy regimens that include cisplatinum.

**Synonyms:** - Carcinoma, Yolk Sac - Endodermal Sinus Neoplasm - Endodermal Sinus Neoplasm - Endodermal Sinus Tumor - Endodermal Sinus Tumor - Endodermal sinus tumor - YOLK SAC TUMOR, MALIGNANT - Yolk Sac Neoplasm - Yolk Sac Neoplasm - Yolk Sac Tumor Site Unspecified - Yolk Sac Tumour Site Unspecified - Yolk sac tumor