Does multidetector computed tomographic urography (MDCTU) T staging classification correspond with pathologic T staging in upper tract urothelial carcinoma?

Purpose: Multidetector computed tomographic urography (MDCTU) is not yet sufficient to be used in the clinical staging of upper tract urothelial carcinoma (UTUC). This study aimed to compare the diagnostic accuracy of MDCTU T stage classification and pathologic T staging for UTUC.

Methods: We retrospectively evaluated 125 patients with UTUC who underwent preoperative MDCTU. A single radiologist classified the MDCTU pattern of the tumors as either low or advanced T stage for localized or locally advanced tumors, respectively. The diagnostic values of MDCTU for locally advanced tumors and the kappa agreement between MDCTU and pathologic T stage were investigated.

Results: Among 85 pathologic low T stage (Ta-T2) tumors, 71 low T stage tumors were correctly detected by MDCTU, while 30 out of 40 advanced T stage (T3-T4) tumors were correctly diagnosed by MDCTU. MDCTU led to under-staging in 8% (10/125) tumors and over-staging in 11.2% (14/125) tumors. Therefore, the overall accuracy of MDCTU in the diagnosis of low and advanced T stage tumors was 80.8% (101/125 patients). The sensitivity for advanced T stage tumors was 75% (30/40), the specificity was 83.5% (71/85), and the positive and negative predictive values were 68.1% (30/44) and 87.6% (71/81), respectively. The kappa agreement value between the MDCTU T stage and pathologic T stage was 0.57 (95% confidence interval (CI) 0.42-0.72), which was statistically significant (P = 0.001).

Conclusion: MDCTU T stage classification may be relatively accurate for the detection and staging of UTUC correspondence with a pathologic stage.