Could EUS be useful for evaluating right renal vein and inferior vena cava thrombosis due to renal cell carcinoma? Report of 3 cases.

Background: More than 200,000 new cases of kidney cancer are diagnosed annually. The reported incidence of inferior vena cava (IVC) involvement in patients with renal-cell carcinoma (RCC) ranges from 4% to 10%. Standard imaging modalities are unable to distinguish the inner structure of a thrombus and whether the vessel wall is invaded.

Objective: To assess the utility of EUS for investigating IVC thrombosis because of RCC, particularly the thrombus characteristics and the involvement of the IVC, and the right and left renal veins.

Design, Setting, And Patients: EUS was used to investigate 3 patients with RCC and IVC involvement. The endosonographer was blinded to the results of other imaging techniques.

Interventions: A diagnostic EUS was performed with the patient under deep sedation (propofol) in 2 patients, and the third patient was given midazolam and fentanyl intravenously.

Main Outcome Measurement: EUS identified a possible neoplastic invasion of the renal veins and/or IVC, distinguishing between the neoplastic hypoechoic and non-neoplastic hyperechoic thrombus in the IVC lumen and indicated the solidity of the inner structure of the clot.

Results: EUS is useful in the vascular staging of RCC with suspected neoplastic involvement and thrombosis of either the renal veins, the IVC, hepatic veins, or the right atrium. EUS helped establish the consistency of the IVC thrombus and provided useful information to the surgeon for planning the use of a temporary, intraoperative caval filter.

Limitations: The limitation of this study was the small number of patients. More cases are needed before stating that EUS could be useful in the staging of the neoplastic thrombi because of RCC.

Conclusions: Diagnostic EUS can help in the detection and the staging of IVC thrombosis because of RCC. Further data are needed to evaluate its real impact on surgical management.