[Induction chemotherapy and radical resection for primary nonseminomatous mediastinal germ cell tumor (NSGCT); report of a case].

A 15-year-old male was admitted to our hospital for treatment of an anterior mediastinal tumor. The tumor was visualized by chest radiography 3 months prior to admission. Computed tomography (CT) revealed a heterogeneous solid tumor located in the anterior mediastinum. Although CT-guided needle biopsy had been performed twice, histologic diagnosis could not be confirmed. We believed this tumor to be nonseminomatous mediastinal germ cell tumor (NSGCT) and started intensive chemotherapy with cisplatin (CDDP) without histologic diagnosis because his serum AFP level was rapidly increasing. After 2 courses of chemotherapy, his serum AFP level returned to the normal range and surgical resection of the tumor with part of right lung was performed. Histopathological examination revealed that the tumor consisted of mature teratoma and yolk sac tumor. He underwent 1 course of chemotherapy post-operatively because a small number of viable cells were histopathologically recognized in the yolk sac component. At the time of writing, the patient is alive without any evidence of recurrence.