Diagnostic Accuracy of Qualitative and Quantitative Computed Tomography Analysis for Diagnosis of Pathological Grade and Stage in Upper Tract Urothelial Cell Carcinoma. Issue 2 (March 2018) - Mammen, Suraj
Abstract : Objective: The aim of this study was to compare grade and stage of upper tract urothelial cell carcinoma (UCC) using computed tomography. Materials and Methods: With institutional review board approval, 48 patients with 49 UCC (44 high grade and 5 low grade, 26 ⩽ T1 and 23 ≥ T2) underwent nephroureterectomy and preoperative computed tomography between 2013 and 2015. Two blinded radiologists assessed for tumor appearance (filling defect/mass or wall thickening/stricture), margin (smooth or spiculated/irregular), texture (homogeneous, heterogeneous), hydronephrosis, and calcification. A third blinded radiologist established consensus. A fourth blinded radiologist measured size and first-order histogram texture features. Comparisons were performed using χ 2 test, multivariable logistic regression, and receiver operator characteristic analysis. Results: There was no difference in size of tumors compared by grade or stage ( P = 0.80 and 0.13, respectively). Among subjective variables, only tumor texture was significantly different between low- and high-grade UCC ( P = 0.03; κ = 0.45). Tumors characterized as spiculated/irregular margin ( P = 0.003; 0.30) and heterogeneous ( P < 0.001; κ = 0.45) were associated with T2 disease or higher. Entropy was greater in higher grade (6.23 ± 0.46 vs 5.72 ± 0.28) and T2 disease or higher (6.40 ± 0.33 vs 5.95 ± 0.48), ( P = 0.03 and 0.02, respectively) with no differences in Kurtosis or Skewness ( P > 0.05). Area under the receiver operator characteristic curve for entropy to diagnose high-grade and T2 tumors or higher was 0.83 (confidence interval, 0.64–1.0) and 0.79 (confidence interval 0.59–0.98), respectively. Conclusions: Heterogeneity, assessed qualitatively and quantitatively, is accurate for diagnosis of higher grade and stage of disease in upper tract UCC. Spiculated/irregular margins are also associated with T2 disease or higher.