[Retroperitoneal extragonadal germ cell tumors: apropos of 4 cases. The importance of research of an occult testicular lesion].

In the absence of palpable testicular tumor one often retains the primitive character of an extragonadal germ-cell tumor with retroperitoneal localization. This motion must be reconsidered in front of the occasionally late discovery of the scrotal origin of those lesions. The usefulness of testicular sonography in the revelation of infra clinical lesions is now perfectly well admitted. Concurrently, testicular biopsies can provide the notion of carcinoma in situ and its links with the retroperitoneal germ-cell tumor must be indicated precisely. The four related observations allow us to stress on the seriousness of this affection which often remains tardily diagnosed. The specific treatment of the testicular lesion, when it is put into evidence, turns out to be absolutely necessary.