[Transitional cell carcinoma of the upper urinary tract- staging by computed tomography].

Purpose: To determine the accuracy of computed tomography (CT) in staging transitional cell carcinoma of the renal pelvis and calyces and to identify whether hydronephrosis proximal to the tumor used as a criterion for minimal invasion may improve the overall accuracy of the method.

Materials And Methods: 24 patients with transitional cell carcinoma of the upper urinary tract underwent preoperative CT. In all cases nephroureterectomy was performed and CT and pathologic staging were compared.

Results: Pathologic staging revealed two stage I tumors, eight stage II tumors, five stage III tumors, and 9 stage IV tumors. The initial overall CT staging accuracy was 66.66% (16 of 24 patients). Reevaluation of the CT studies by using proximal hydronephrosis as a criterion for minimal invasion improved the overall CT staging accuracy (83.33%).

Conclusions: When CT demonstrates direct tumor extension through the pelvic wall, it is a sensitive indicator of high-stage tumor. Hydronephrosis proximal to the tumor may cause overstaging of stage 0-II disease.