Leiomyosarcoma of the inferior vena cava. Ultrasonographic appearance.

Ultrasonographic features of six leiomyosarcomas of the inferior vena cava are described. In most cases, the presentation is typical enough to strongly suggest the histologic diagnosis. The tumor is usually greater than 10 cm long, hypoechoic, heterogeneous. Cystic components can be found. It is sharply demarcated from neighboring organs which are displaced. The mass is located at the very place of the inferior vena cava, the lumen of which is no longer seen. It is fusiform shaped, surprisingly sparing the aorta. Differential diagnosis along with other radiologic examinations, pathologic findings, and prognosis are discussed.