Computerized tomography for detection and staging of localized and pathologically defined upper tract urothelial tumors.

Between 1980 and 1989, 94 patients were evaluated for upper tract urothelial tumors. Preoperative computerized tomography (CT) scans and pathology reports were available in 30 patients who also had nephroureterectomy for treatment of transitional cell carcinoma. Retrospective evaluation of these CT scans was done without knowledge of the final pathological status to determine accuracy of tumor detection and staging. Pathological findings were also reviewed and the pathological staging was compared to that of CT. At pathological evaluation the 30 renal units contained 34 grossly visible, distinct papillary tumors: 7 were ureteral and 27 were in the renal pelvis. Of the renal units 8 also contained carcinoma in situ that was not visible on any study. Conventional excretory urograms and/or retrograde or antegrade pyelograms detected 28 (82%) and CT 17 (50%) of the 34 papillary tumors. Excluding suboptimal scans due to early generation machines, inadequate intravenous contrast medium or too widely spaced slices caused CT sensitivity to increase to 15 of 22 (68%). It was not possible to distinguish stages Ta to T2 lesions on any radiological study. CT sensitivity for parenchymal invasion was 75% with a specificity of 43%. CT sensitivity for fat invasion was 67% with a specificity of 44%. We conclude that CT is limited in usefulness for detection and staging of low stage upper tract urothelial tumors. While CT is the best current imaging modality over-all for staging of upper tract urothelial tumors, results obtained in low stage tumors must be viewed with caution particularly when precise preoperative clinical staging is essential, such as before nephron-sparing procedures.