The accuracy of multidetector computerized tomography for evaluating tumor thrombus in patients with renal cell carcinoma.

PURPOSE: New advances in computerized tomography, including multidetector computerized tomography with 3-dimensional reformatting has recently called into question the absolute need for magnetic resonance imaging for evaluating renal cell carcinoma with suspected venous involvement. We assessed the accuracy of multidetector computerized tomography for predicting tumor thrombus and the level of venous involvement in patients with renal cell carcinoma.

MATERIALS AND METHODS: We retrospectively reviewed clinical and pathological features in 41 patients with renal cell carcinoma who underwent staging multidetector computerized tomography before surgery. Multidetector computerized tomography findings regarding the presence and level of tumor thrombus were compared to findings at surgery and at final pathological evaluation. All multidetector computerized tomography studies were read by a single radiologist (EKF) before surgery.

RESULTS: When excluding patients with segmental venous involvement only, the concordance rate between multidetector computerized tomography and pathological findings was 84%. Multidetector computerized tomography accurately predicted the level of tumor thrombus in 26 of 27 patients (96%). Four cases of negative multidetector computerized tomography findings were up staged to renal vein involvement based on pathological findings. All 4 patients had early distal thrombi that did not change operative management.

CONCLUSIONS: Multidetector computerized tomography with 3-dimensional mapping is an effective imaging modality for accurately characterizing the level of venous thrombus in patients with renal cell carcinoma. This modality effectively identified patients with clinically significant venous thrombus. Patients with renal cell carcinoma in whom multidetector computerized tomography fails to detect tumor thrombus are unlikely to have a tumor thrombus found at surgery that would change the surgical approach.