PRIMARY EXTRAGONADAL GERM-CELL TUMORS OF THE RETROPERITONEUM - DIFFERENTIATION OF PRIMARY AND SECONDARY TUMORS

Primary extragonadal germ cell tumors (EGCTs) of the retroperitoneum a re rarely encountered. In most cases, they arise from remnants of the genital ridge, whereas the majority of retroperitoneal germ cell tumor s are metastases from primary testicular tumors. Differentiating betwe en these primary and secondary tumors can be difficult because gonadal germ cell tumors can regress or develop slowly. Careful examination o f the testes with ultrasound (US) is crucial for this determination, b ut asynchronous or metachronous lesions in both the testes and retrope ritoneum can occur. Symptoms are often nonspecific, and diagnosis is f requently delayed. Serum markers such as beta-human chorionic gonadotr opin and alpha-fetoprotein are often helpful in the diagnosis and foll ow-up of these tumors. Imaging techniques such as US and computed tomo graphy play a major role in the localization and differentiation of pr imary and secondary retroperitoneal EGCTs. Treatment of EGCTs usually requires a combination of surgery, irradiation, and chemotherapy.