case_images: PMC4732999_01
case_images: Axial abdominal computed tomographic scan showing (A) focal mass of fat attenuation in the right kidney and the right renal vein and (B) hyopattenuated tumor thrombus in the inferior vena cava.
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case_images: PMC4732999_01_gr1.jpg
case_images: fig1
case_images: Computed tomographic (CT) scan of the abdomen confirmed a 3-cm right upper pole renal mass with central fat attenuation and a 5-cm level II IVC thrombus (extension into the right renal vein and IVC below the level of the hepatic veins; Fig. 1A and B).
case_images: (A) Gross specimen of the right kidney showing lipomatous tumor thrombus in the renal vein. (B) Hematoxylin and eosin stain of angiomyolipoma showing 3 components: abnormal thick-walled blood vessel, spindle cells spinning of the vessel wall, and mature adipose tissue.
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case_images: PMC4732999_01_gr2.jpg
case_images: fig2
case_images: There was a 6.8 x 0.9 cm tumor thrombus protruding through the renal vein, without involvement of the vein wall (Fig. 2A). Microscopic examination revealed a tumor composed of adipose tissue predominantly, scattered thick-walled blood vessels, and minor smooth muscle cells surrounding abnormal vessels (Fig. 2B).