Extragonadal retroperitoneal germ cell tumors without apparent testicular involvement. A search for the source.

Extratesticular germ cell neoplasms without apparent testicular primary tumors are rare. The origin of these neoplasms has been debated in the literature for decades. With the advent of effective chemotherapy for extratesticular germ cell neoplasms, the origin of these tumors becomes more than academic. We report on 3 cases of retroperitoneal germ cell neoplasms with microscopic intratesticular primary tumors. All patients with extragonadal germinal cell tumors of the testes should undergo thorough investigation for an occult testicular primary tumor despite a normal testis examination. We review previously reported cases of extratesticular germ cell neoplasms without an apparent testicular primary tumor.