[A case of metachronal testicular tumor eight years after medical treatment of extragonadal germ cell tumor].

A 22-year-old man was admitted to our hospital complaining of a left cervical mass. Computed tomography (CT) showed multiple enlarged lymph nodes at the left cervical vein and para-aortic areas. Histological examination of a biopsy indicated an embryonal carcinoma. The levels of human β-chorionic gonadotropin (β-HCG) and lactic dehydrogenase (LDH) were both elevated. Ultrasonography revealed testicular calcification, but there were no findings on magnetic resonance imaging (MRI). The patient was diagnosed as having an extragonadal germ cell tumor. After four courses of chemotherapy with BEP protocol (bleomycin, etoposide and cisplatin), retroperineal lymph node dissection (RPLND) was performed and there was no involvement of the viable cells in the resected lymph nodes. Eight years after chemotherapy, he noticed an enlargement of his left scrotum without pain. β-HCG was again elevated. A unilateral high orchiectomy was performed, and histology revealed a seminoma. He was staged as pT1N0M0S0. Six months later he remains disease-free.