Upper Urinary Tract Transitional Cell Tumors Diagnosis: Role of CT- Urography

Objective: The purpose of this study was to point out CT Urography (CTU) potentials and limitations for the diagnosis of Upper Urinary Tract Transitional Cell Carcinoma (UUT-TCC) and to suggest how and when to use invasive second-line investigations. Materials and Methods: 66 patients with a suspected UUT-TCC were examined with CTU; 52/66 patients underwent also Retrograde Pielography (RP). Reference standards were histopathology and the 24-month clinical and imaging follow-up. Moreover the T stage of 15 tumors, treated by surgery, was assessed. Results: 21/66 patients had a final diagnosis of UUT-TCC; CTU showed a sensitivity of 90.5%, a specificity of 84.4%, a Positive Predictive Value (PPV) of 73.1% and a Negative Predictive Value (NPV) of 95%. The overall accuracy of CTU in evaluation of T parameter was 80%. In the subgroup of 52 patients, CTU and RP showed both a sensitivity of 85.7%, a specificity respectively of 84.4% and 82.2%, a PPV of 46.2% and 42.8%, a NPV of 97.4% and 97.3%. In 7 cases, false positive both at CTU and RP, biopsy allowed a definitive diagnosis of tumor absence. Moreover in 1 case, false negative both at CTU and RP with positive urinary cytology, endoscopy and biopsy showed a small superficial tumor. Conclusion: CTU, complemented by urinary cytology and cystoscopy, is the technique of choice for UUT-TCC diagnosis and staging. In cases of positive CT findings, RP-guided biopsy is advisable to complete the diagnostic work-up; nevertheless, if CTU is negative and cytology is positive, endoscopy is indicated.