Yolk sac tumors (endodermal sinus tumors) of the extracranial head and neck regions

Yolk sac tumors (or endodermal sinus tumors) are rare neoplasms of germ cell origin that have been reported in gonadal sites (testis and ovary). Extragonadal yolk sac tumors are uncommonly seen, and in particular, they are rare in the extracranial head and neck regions; we found 27 well-documented cases in the English-language literature. We discuss their clinical and pathologic features.