RESUMEN
BACKGROUND: Testicular germ-cell carcinoma is the most frequent neoplasm in males aged 15 to 35 years old. It is bilateral in 2% to 3%, and synchronous in 20% to 25% of the cases. CLINICAL CASE: The case is presented of a 19 year-old male, with abdominal pain. Physical examination revealed abdominal mass in the umbilical region, and the computed tomography scan showed a retroperitoneal tumour, with α-fetoprotein, lactate dehydrogenase, and human chorionic gonadotropin above limits. Testicular ultrasound showed bilateral lesions. Exploratory laparotomy was performed, identifying an unresectable retroperitoneal tumour. Biopsies were taken, reporting mixed germ cell tumour composed of choriocarcinoma and embryonal carcinoma. Six cycles of chemotherapy were given, based on bleomycin, etoposide and cisplatin, with partial tumour response. Later on, the patient underwent bilateral radical orchiectomy, with pathology reporting a synchronous bilateral testicular teratoma. A second line of chemotherapy was given, based on vincristine, etoposide, ifosfamide and cisplatinum. Nevertheless, the disease progressed, with metastatic dissemination and the patient died. DISCUSSION: Germ cells tumours can present in primary extra-gonadal locations. It is difficult to distinguish a retroperitoneum primary germ cell tumour from metastatic disease of a clinically undetected gonadal tumour or one that has regressed, like the situation described in the case presented. CONCLUSIONS: Ninety percent of patients diagnosed with germ cell tumours can be cured. However, delay in diagnosis correlates with an advanced clinical stage and poor prognosis.