Multislice computed tomography in planning nephron-sparing surgery in a prospective study with 76 patients: comparison of radiological and histopathological findings in the infiltration of renal structures

The aim of this prospective study is to determine the diagnostic accuracy of multidetector-row computed tomography (CT) compared to histopathologic findings in tumor staging of renal cell carcinoma, with the focus on tumor stage, vein and artery infiltration, and infiltration of the renal pelvis. In a prospective study, a total of 76 consecutive patients with suspected renal cell carcinoma were preoperatively assessed for tumor staging using multidetector-row CT. Triphasic CT imaging (i.e., noncontrast, arterial, and parenchymal phase) was performed using multidetector-row CT with reconstructed slice thicknesses of 2 and 5 mm. Two blinded readers evaluated the CT scans independently; the results were then correlated with the histopathologic results. A total of 56 renal cell carcinomas were proven on histopathology. Readers 1 and 2 reached a sensitivity of 1.0 and 1.0 and a specificity of 0.41 and 0.42 for arterial infiltration, a sensitivity of 1.0 and 0.86 and a specificity of 0.58 and 0.5 for venous infiltration, and a sensitivity of 0.75 and 1.0 and a specificity of 0.5 and 0.44 for infiltration of the renal pelvis. The correlation between both readers was 0.7 for all modalities. The multiplanar reconstruction capability of multidetector-row CT allowed good sensitivity in predicting arterial infiltration. The lowest specificity was reached in excluding infiltration of the renal pelvis. Despite its high temporal and spatial resolution, the capacity of multidetector CT to predict intrarenal infiltrations is still limited.