Oral metastasis of the mediastinal germ cell tumor (yolk sac).

A yolk sac tumor is a rare malignant tumor of germ cell origin. It most commonly arises from the testes and ovaries in young adults, but extragonadal sites of origin are reported in 10% to 15% of the cases. Yolk sac tumors are malignant, tend to recur locally, and may present with widespread metastases at the time of diagnosis. Involvement of the head and neck is uncommon. In this study, we present the case of a 23-year-old man presenting with mandibular and adjacent gingival metastasis of a mediasatinal yolk sac tumor. Thus, the patient has already undergone chemotherapy; no additional treatment was provided. In this case report, clinical and histopathologic features of the oral metastases of a yolk sac tumor were briefly discussed.