Endodermal sinus (yolk sac) tumor of oral cavity originating from gingiva.

Endodermal sinus tumor is a malignant germ cell tumor which usually arises in gonads. Extragonadal endodermal sinus tumors in the head and neck are very rare. Here a gingival endodermal sinus tumor is reported. The lesion demonstrated typical microscopic features of the endodermal sinus tumors of gonads. The tumor cells showed alpha-fetoprotein immunoreactivity in immunohistochemical evaluation. The serum alpha-fetoprotein level was high. This is the first gingival case in the related literature.