[Case report: simultaneous bilateral testicular tumors with different cell types].

A 29-year-old man was admitted to our hospital due to bilateral testicular tumors. The bilateral testicular tumors were palpated and visualized by ultrasound and magnetic resonance imaging (right 8 cm, left 6 cm in diameter). Bilateral high orchiectomies were performed after frozen storage of the sperm. Pathological examination revealed seminoma and immature teratoma in the right testis and seminoma in the left testis. Three months later, computed tomography (CT) showed multiple metastatic lung nodules. In addition, positron emission tomography (PET)-CT examination revealed peri-caval lymph node metastasis together with the lung metastases. Lung metastases disappeared, but the lymph node metastasis reduced and remained after 3 courses of combination chemotherapy with bleomycin, etoposide and cisplatin. PET-CT examination revealed that no uptake of FDG was seen in the lung and lymph nodes. Retroperitoneal lymph node dissection was performed. No viable tumor cells were histologically present in the excited lymph nodes. The postoperative course was good and uneventful at 10 months under androgen replacement therapy without disease recurrences.