A mediastinal somatic-type germ cell tumor with hepatic metastasis successfully treated by multiple modalities.

Rhabdomyosarcoma in the mediastinum coexisting with metastatic non-seminomatous germ cell tumor, so-called somatic-type malignancy, is a rare carcinoma and has poor survival. This study reports a case of diffuse and huge hepatic metastasis of non-seminomatous germ cell tumor associated with coexisting embryonal rhabdomyosarcoma in the mediastinum. A 31-year-old man presented with abdominal pain and was found to have multiple abnormal hepatic masses on abdominal computed tomography (CT). Concomitantly, an anterior mediastinal mass was found on chest CT. Chemotherapy was initiated because the hepatic lesion was diagnosed as choriocarcinoma, based on histological findings and the elevation of chorionic gonadotropin β-subunit and α-fetoprotein. After six cycles of bleomycin, etoposide and cisplatin chemotherapy the metastatic liver tumors showed complete response. The remaining mediastinal tumor was completely and successfully resected. The histological findings revealed mature teratoma with embryonal rhabdomyosarcoma. The patient has remained well for over six years after the treatment without any signs of disease recurrence.