Preoperative magnetic resonance imaging of vena caval tumor thrombi: experience with 5 cases.

Magnetic resonance scans were performed preoperatively in 5 patients who underwent surgical removal of renal or adrenal tumors with direct extension of the tumor into the vena cava. Of the patients 4 had renal cell carcinoma and 1 had adrenocortical carcinoma. Magnetic resonance imaging staged correctly the level of vena caval tumor thrombus involvement in 4 patients and missed the presence of right atrial tumor extension in 1. This noninvasive imaging modality can be used instead of contrast venography in most patients to assess the presence and extent of vena caval tumor involvement by renal cell carcinoma. Contrast venography should be used for those patients with suspected cardiac involvement and for those whose tumor thrombus extent remains unclear after magnetic resonance imaging.