Computed tomography and magnetic resonance imaging of inferior vena caval thrombus associated with metastasis to the kidney

The computed tomography and magnetic resonance imaging findings in 2 cases of inferior vena caval thrombus associated with metastases to the kidney are presented. In both cases, the radiologic findings were suggestive of renal cell carcinoma. Recognition that metastases to the kidney can be associated with inferior vena caval thrombus broadens the differential diagnosis in a patient with a renal mass, an inferior vena caval filling defect, and a known primary malignancy, potentially altering the diagnostic approach.