A 40-year-old woman in the twenty-fifth week of pregnancy presented with a gross retroperitoneal mass. At the end of the pregnancy, the patient was submitted to surgery, and the gross infiltration of the inferior vena cava wall required the resection of the vena cava with its prosthetic substitution. The histopathological examination demonstrated the presence of a leiomyosarcoma of the inferior vena cava. An electronic video supplement showing the most important intraoperative passages is available online at doi:10.1016/j.eururo.2008.06.074.