Primary retroperitoneal seminoma with utrasonically abnormal testes.

Primary retroperitoneal seminomas account for approximately 2% of all seminomas. Differentiating the primary retroperitoneal tumor from a metastatic tumor with an occult testicular primary remains difficult despite the availability of ultrasonic examination. We present a case of primary retroperitoneal seminoma with ultrasonically demonstrated abnormalities in both testes. The patient underwent a unilateral orchiectomy and ultrasound-guided biopsy of the opposite testis. All surgical specimens were negative for testis cancer. Controversial issues in the diagnosis and treatment of primary retroperitoneal germ cell tumors are discussed.