Contrast-enhanced ultrasound in diagnosis of epithelioid renal angiomyolipoma with renal vein and inferior vena cava extension.

Epithelioid angiomyolipoma is considered to be a rare variant of angiomyolipoma and potentially malignant. Reported cases of renal epithelioid angiomyolipoma with extension into the renal vein and inferior vena cava are even rarer. Once it occurs, it is difficult to differentiate from renal cell carcinoma on imaging. In addition, very few of the reported cases presented contrast-enhanced ultrasound images. Here, we report a case of a renal epithelioid angiomyolipoma extending into the renal vein and inferior vena cava along with its contrast-enhanced ultrasonic information. Contrast-enhanced ultrasound provided valuable information for diagnosis in this case.