Retroperitoneal extragonadal germ cell tumor in a patient with Klinefelter's syndrome.

A 22-year-old man was diagnosed with retroperitoneal seminoma associated with Klinefelter's syndrome. The tumor was 14 x 12 cm in size and surrounded the superior mesenteric artery. He received induction chemotherapy with bleomycin, etoposide and cisplatin (BEP) followed by salvage chemotherapy with paclitaxel, ifosfamide and cisplatin (TIP). The tumor considerably decreased in size and remains as a poorly defined plaque. At the time of writing, he is being followed closely and is free from progression.