Mediastinal Yolk Sac Tumor

**Semantic type:** Neoplastic Process

**Definition:** An extragonadal non-seminomatous malignant germ cell tumor that arises from the mediastinum. It is characterized by the presence of small pale cells with small amount of cytoplasm and round to oval nuclei with small nucleoli forming a variety of patterns, including microcystic, macrocystic, pseudopapillary, myxomatous, hepatoid, polyvesicular vitelline, and solid. It manifests with respiratory distress, thoracic pain, fever, and superior vena cava syndrome.

**Synonyms:** - Endodermal Sinus Neoplasm of Mediastinum - Endodermal Sinus Neoplasm of the Mediastinum - Endodermal Sinus Tumor of Mediastinum - Endodermal Sinus Tumor of the Mediastinum - Mediastinal Endodermal Sinus Neoplasm - Mediastinal Endodermal Sinus Tumor - Mediastinal Yolk Sac Neoplasm - Yolk Sac Neoplasm of Mediastinum - Yolk Sac Neoplasm of the Mediastinum - Yolk Sac Tumor of Mediastinum - Yolk Sac Tumor of the Mediastinum