Early-stage clear cell tubulopapillary renal cell carcinoma: imaging features and distinction from clear cell and papillary subtypes

Purpose: Clear cell tubulopapillary renal cell carcinoma (CCTPRCC) is a recently described, low grade subtype of renal cancer. We determined if imaging features could be used to distinguish early-stage CCTPRCC from stage-matched clear cell RCC (ccRCC) and papillary RCC (pRCC). Subjects and Methods: This IRB-approved retrospective study included 54 stage-Ia patients with pathologically-confirmed CCTPRCC (n=18), ccRCC (n=18), and pRCC (n=18). CT (n=48) and MRI (n=27) exams were reviewed and imaging features compared. Continuous variables were evaluated using ANOVA and Tukey's multiple comparison tests. Categorical variables were compared using Chi square test or Fisher's exact test. Results: Compared to pRCC, CCTPRCC had a lower mean attenuation value on unenhanced CT (p<0.017), was more often hyperintense on T2-weighted images (p<0.0001), showed an ill-defined margin (p=0.003), and demonstrated nonenhancing areas (p=0.0003). The presence of all three of these statistically significant features (hypoattenuation [unenhanced attenuation < 25HU], ill-defined margin, nonenhancing areas) yielded an area under the Receiver Operator Curve (ROC) of 0.92 (95% CI: 0.83-0.99) for differentiating CCTPRCC from pRCC. There were no significant differences in the imaging features of CCTPRCC and ccRCC. Conclusions: Early stage clear cell tubulopapillary renal cell carcinoma can be distinguished from papillary RCC based on low attenuation on unenhanced CT, high intensity on T2-weighted images, an ill-defined margin, and presence of nonenhancing areas, but cannot be distinguished from clear cell RCC

Use of Quantitative T2-Weighted and Apparent Diffusion Coefficient Texture Features of Bladder Cancer and Extravesical Fat for Local Tumor Staging After Transurethral Resection

OBJECTIVE. The purpose of this study was to determine whether quantitative T2-weighted imaging and apparent diffusion coefficient (ADC) texture features of bladder cancer and extravesical fat are predictive of muscle invasive bladder cancer (category >= T2) and extravesical (category >= T3) disease after transurethral resection of a bladder tumor (TURBT). MATERIALS AND METHODS. In this retrospective study, 36 patients (27 men, nine women; mean age, 71 years) were identified who underwent post-TURBT MRI followed by cystectomy without intervening treatment from August 2011 through October 2016. Texture features of bladder cancer and extravesical fat adjacent to the tumor on T2-weighted and ADC images were extracted and compared between category = T3 and category T1 versus >= T2 tumors by means of Kruskal-Wallis or Mann-Whitney U test. Multivariate logistic regression analysis was performed, and ROC curves were calculated. RESULTS. Twenty-six of the 36 (72%) tumors were >= T2, and 53% (19/36) were >= T3. In multivariate analysis, bladder cancer entropy on T2-weighted images (p = 0.006; odds ratio [OR], 4.56; 95% CI, L49-20.41; AUC, 0.85) and ADC maps (p = 0.019; OR, 2.24; 95% CI, 1.13-5.31; AUC, 0.80) and extravesical fat entropy on T2-weighted images (p = 0.005; OR, 17.50; 95% CI, 3.01-200.80; AUC, 0.84) and ADC maps (p = 0.002; OR, 6.54; 95% CI, 1.9032.40; AUC, 0.82) remained greater for z T3 than for s T2 tumors. In multivariate analysis, bladder cancer entropy on ADC maps (p = 0.027; OR, 2.11; 95% CI, 1.08-5.03; AUC, 0.76) and extravesical fat entropy on T2-weighted images (p = 0.010; OR, 5.33; 95% CI, 1.25-3.79; AUC, 0.78) and ADC maps (p = 0.029; OR, 3.80; 95% CI, 1.25-16.97; AUC, 0.74) remained greater for category >= T2 compared with category T1 tumors. CONCLUSION. Greater entropy of primary bladder cancers and extravesicular fat was observed in category >= T3 than in category = T2 than in category T1 tumors. MRI texture analysis can help with local bladder cancer staging in patients who have undergone TURBT and may serve as a biomarker for higher local category bladder cancers

Multi-institutional analysis of CT and MRI reports evaluating indeterminate renal masses: comparison to a national survey investigating desired report elements

© 2018 Springer Science+Business Media, LLC, part of Springer Nature Purpose: To determine the need for a standardized renal mass reporting template by analyzing reports of indeterminate renal masses and comparing their contents to stated preferences of radiologists and urologists. Methods: The host IRB waived regulatory oversight for this multi-institutional HIPAA-compliant quality improvement effort. CT and MRI reports created to characterize an indeterminate renal mass were analyzed from 6 community (median: 17 reports/site) and 6 academic (median: 23 reports/site) United States practices. Report contents were compared to a published national survey of stated preferences by academic radiologists and urologists from 9 institutions. Descriptive statistics and Chi-square tests were calculated. Results: Of 319 reports, 85% (271; 192 CT, 79 MRI) reported a possibly malignant mass (236 solid, 35 cystic). Some essential elements were commonly described: size (99% [269/271]), mass type (solid vs. cystic; 99% [268/271]), enhancement (presence vs. absence; 92% [248/271]). Other essential elements had incomplete penetrance: the presence or absence of fat in solid masses (14% [34/236]), size comparisons when available (79% [111/140]), Bosniak classification for cystic masses (54% [19/35]). Preferred but non-essential elements generally were described in less than half of reports. Nephrometry scores usually were not included for local therapy candidates (12% [30/257]). Academic practices were significantly more likely than community practices to include mass characterization details, probability of malignancy, and staging. Community practices were significantly more likely to include management recommendations. Conclusions: Renal mass reporting elements considered essential or preferred often are omitted in radiology reports. Variation exists across radiologists and practice settings. A standardized template may mitigate these inconsistencies