Staging of renal cell carcinoma by dynamic computed tomography: a prospective comparison of two techniques

Two dynamic computed tomographic methods used for staging renal carcinoma in 46 patients are described and compared. Twenty-eight patients were examined using an infusion technique during incremental dynamic scanning across the kidneys with contrast administered via an arm vein. Eighteen patients were staged using a technique comprising a single location dynamic scan sequence at the level of the renal hilum followed by an incremental sequence during an infusion of contrast into the femoral vein. When compared with overall pathological staging, the arm vein infusion technique correctly staged 20 patients (72%) with four patients (14%) understaged and four (14%) overstaged. The femoral vein infusion and single location dynamic scanning technique correctly staged 11 (61%) patients with three (17%) overstaged and four (22%) understaged. The femoral vein infusion with single location scanning was more accurate in demonstrating tumour involvement of the renal vein (83.3% correct vs. 78.6%), inferior vena cava (94.4% correct vs. 89.3%) and lymph nodes (88.9% correct vs. 78.6%) but was less accurate in assessing extracapsular spread (77.8% correct vs. 96.4%). The additional information obtained from the single location dynamic sequence is sufficiently valuable for this part of the second technique to be used in any scanning protocol for staging renal carcinoma.