Mixed nonseminomatous germ cell tumor presenting as a subcutaneous tissue mass

Extragonadal germ cell tumors most commonly arise in the midline of the retroperitoneum or the mediastinum. Primary tumors involving the skin are very rare. Only one case of malignant primary germ cell tumor located in the skin has been reported. We present the case of a 44-year-old white man with a primary subcutaneous mixed nonseminomatous germ cell tumor. This man had a long-lasting subcutaneous lump of the breast, which became painful. Surgery revealed 3 juxtaposed nodules. Microscopic examination showed a mixed germ cell tumor with a 90% immature teratoma component and a 10% embryonal carcinoma component. Testicular ultrasound and computed tomography of the chest, abdomen, pelvis, and brain were normal. Serum human chorionic gonadotrophin, beta-human chorionic gonadotrophin, alpha-fetoprotein, and lactate dehydrogenase were within normal ranges. A further surgical excision was performed. The patient is presently alive with no evidence of disease after a follow-up of 7 years. Review of the literature indicates that primary cutaneous extragonadal germ cell tumors usually occur as cutaneous or subcutaneous solitary nodules or as ulcerated lesions. They mainly consist of mature teratomas in children. Only 2 cases have been reported in adults.