Gevork N Mnatzakanian1,2, Atul B Shinagare3,4, V Anik Sahni3, Michelle S Hirsch5, Stuart G Silverman3. 1. Department of Radiology, Brigham and Women's Hospital, 75 Francis St, Boston, MA, 02115, USA. mnatzakanian@smh.ca. 2. Department of Medical Imaging, St. Michael's Hospital, 3-141CC, 30 Bond St., Toronto, ON, M5B 1W8, Canada. mnatzakanian@smh.ca. 3. Department of Radiology, Brigham and Women's Hospital, 75 Francis St, Boston, MA, 02115, USA. 4. Dana-Farber Cancer Institute, 450 Brookline Ave, Boston, MA, 02215, USA. 5. Department of Pathology, Brigham and Women's Hospital, 75 Francis St., Amory-3, Boston, MA, 02115, USA.
Abstract
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). METHODS: This IRB-approved retrospective study included 54 stage T1a 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 ≤25 HU), 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.
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). METHODS: This IRB-approved retrospective study included 54 stage T1a 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 ≤25 HU), 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.
Entities:
Keywords:
CT and MRI features; Clear cell tubulopapillary renal cell carcinoma; Renal cell carcinoma subtype; Renal mass
Authors: Alberto Diaz de Leon; Ali Pirasteh; Daniel N Costa; Payal Kapur; Hans Hammers; James Brugarolas; Ivan Pedrosa Journal: Radiographics Date: 2019-06-14 Impact factor: 5.333