Bibliogr. s. 91

Background: Abdominal germ cell tumors are neoplasms which originate from the primary germ cells. Diagnostic imaging (US, CT and MRI) can detect and localize the tumor as well as show its structure. We present two cases of germ cell tumors, which, despite very good imaging in sonography and CT, caused problems in final diagnosis. Case report: In a boy, a polycyclic tumor of the liver hilus was detected. In a girl, two tumors in the pelvis and a few others in the retroperitoneal space were detected. Lymphoma, neuroblastoma and PNET tumors were included in the differential diagnosis. In case of clinical suspicion of an abdominal tumor, including germ cell tumors, diagnostic imaging should begin with sonography. Conclusions: Replacing CT, which is not charged with ionizing radiation, with MRI, especially in monitoring of the treatment effects, should be considered. The ultimate diagnosis of the tumor type must be established on the basis of histopathological examination.