Renal angiomyolipoma with coexistent hemorrhagic aneurysm formation and fatty thrombus in inferior vena cava: a rare presentation.

Angiomyolipoma (AML) is known as the most common benign mesenchymal tumor of kidney. Usually AMLs present as benign lesions without local invasion or complication. However, few cases of renal AML have been reported with complications such as tumor thrombus extension into inferior vena cava (IVC) or hemorrhagic aneurysm formation. We report a complicated case of renal AML with CT and angiography evidence of hemorrhagic aneurysm formation and IVC thrombus, treated by a combination of selective arterial embolization, radical nephrectomy and thrombectomy. Radiologists and clinicians should be aware that AMLs could have such aggressive behaviors.