Tumor thrombus: incidence, imaging, prognosis and treatment

Abstract

Intravascular tumor extension, also known as tumor thrombus, can occur in many different types of cancer. Those with the highest proclivity include Wilm's tumor, renal cell carcinoma (RCC), adrenal cortical carcinoma (ACC) and hepatocellular carcinoma (HCC). The presence of tumor thrombus markedly worsens prognosis and impacts treatment approach. Imaging plays a key role in its diagnosis. Endovascular methods also play a large role in treatment.

Keywords: Tumor thrombus; hepatocellular carcinoma (HCC); renal cell carcinoma (RCC).

Figure 1

A 54-year-old woman with hematuria and a right renal mass (black circle). Tumor thrombus extends into the right renal vein (solid white arrow) and the IVC (dotted black arrow). Note the pelvic varicosities (solid black arrow) and enlarged left gonadal vein (dotted white arrow), which are secondary to IVC obstruction.

Figure 2

A 72-year-old man with cryptogenic cirrhosis found to have large right lobe of liver HCC with extensive portal vein invasion. Tumor thrombus extends into branches of the right portal vein (white arrows) as well as the main portal vein (white asterisk). This T2 weighted MRI shows relative hyperintensity of the portal veins. Normal patent portal vein would show hypointensity secondary to flow void. He underwent treatment with Y-90 embolization.

Figure 3

Different sequence from the same patient as Figure 2. Contrast MRI in the arterial phase shows early arterial enhancement in the thrombosed main portal vein differentiating it from bland thrombus. Main portal vein tumor thrombus is classified as Shi type III.

Figure 4

A 70-year-old man with alcoholic cirrhosis and previously ablated segment V lesion who on follow-up imaging was found to have an infiltrative lesion in segments VI/VII (solid black arrow) with portal vein tumor thrombus (dotted white arrow). Note the patent portal vein (curved black arrow). Bland tumor thrombus is present in the periphery of the right lobe (solid white arrows).

Figure 5

A 48-year-old female with new onset hypertension and palpitations who underwent CT abdomen was done which showed a right adrenal mass (solid black arrow) invading the IVC (dotted black arrow). She subsequently underwent an endocrinology work-up and was found to have elevated catecholamine’s consistent with a pheochromocytoma.