RADIOLOGIC CHARACTERISTICS OF COMPUTERIZED TOMOGRAPHY ATTENUATION IN RENAL CELL CARCINOMA
DOI:
https://doi.org/10.55374/jseamed.v6i0.117Keywords:
renal cell carcinoma, attenuation, Hounsfield unit, kidney, cancerAbstract
Background: Renal cell carcinoma (RCC) is the most common kidney cancer in adults. Computed Tomography (CT) with contrast study is used to diagnose RCC. The enhancement in the nephrogenic phase more than 15 Hounsfield units (HU) is suspected of RCCs. However, this threshold HU shows 15-20% false positive results for RCCs.
Objectives: This study aimed to determine RCC enhancement in CT that was below the standard threshold and to analyze the attenuation range of RCCs in noncontrast CT. Methods: Patients with pathological RCC and undergoing CT with contrast study were retrospectively reviewed. An average of attenuation values of three regions of interest (ROI) were measured in noncontrast and nephrogenic phases, by avoiding foci of calcification and peritumoral region. ROI values were calculated for enhancement and range of attenuation values in the noncontrast CT.
Results: A total of 152 pathologically RCCs were included in the study. Mean ± SD attenuation values were 32.54 ± 8.02 HU (range 13.3-57.23 HU) and 71.26 ± 33.1 HU (range 16.87-202.8 HU) for noncontrast and contrast CT, respectively. Thirty-one (20.4%) of RCCs did not reach 15 HU enhancement. Using multivariate analysis, significant differences among subtypes (p<0.001) and renal mass less than 7 cm (p<0.001) were observed. In noncontrast CT, using a range of 20-60 HU, 129 (84.9%) RCCs were entirely within this range. To improve the accuracy of RCC diagnosis, the combined use of both non-contrast attenuation group (<20 HU and >20 HU) and enhancement >15 HU could increase the accuracy to 96.7%.
Conclusion: One-fifth of RCCs did not reach the standard enhancement threshold that were mostly found in nonclear cell subtype. Especially, when the mass was larger than 7 cm or involved nonclear cell RCCs, the enhancement threshold >15 HU must be carefully used for diagnosis. Using a noncontrast phase regardless HU combined with enhancement >15 HU could improve the accuracy of RCC diagnosis.
Metrics
References
Ljungberg B, Albiges L, Abu-Ghanem Y, Bensalah K, Dabestani S, Fernández-Pello S, et al. European Association of Urology Guidelines on renal cell carcinoma: The 2019 Update. Eur Urol. 2019; 75: 799-810. DOI: https://doi.org/10.1016/j.eururo.2019.02.011
SEER Cancer Stat Facts: Kidney and renal pelvis cancer, Bethesda, MD: National cancer Institute; Available at: http://seer.cancer.gov/statfacts/html/kidrp.html. Accessed May 17, 2022.
Gudbjartsson T, Thoroddsen A, Petursdottir V, Hardarson S, Magnusson J, Einarsson GV. Effect of incidental detection for survival of patients with renal cell carcinoma: results of population-based study of 701 patients. Urology 2005; 66: 1186-91. DOI: https://doi.org/10.1016/j.urology.2005.07.009
Pickhardt PJ, Hanson ME, Vanness DJ, Lo JY, Kim DH, Taylor AJ, et al. Unsuspected extracolonic findings at screening CT colonography: clinical and economic impact. Radiology 2008; 249: 151-9. DOI: https://doi.org/10.1148/radiol.2491072148
Campbell SC, Lane BR. Malignant renal tumors. In: Wein AJ, Kavoussi LR, Partin AW, Peters CA editors. Campbell-Walsh Urology. 11th ed. Philadelphia: Elsevier; 2016. p.1315-64.
Harbi FA, Tabatabaeefar L, Jewett MA, Finelli A, O’Malley M, Atri M. Enhancement threshold small (<4 cm) solid renal masses on CT. Am J Roentgenol 2016; 206: 554-8. DOI: https://doi.org/10.2214/AJR.15.14806
Corcoran AT, Russo P, Lowrance WT, Asnis-Alibozek A, Libertino JA, Pryma DA, et al. Review of contemporary data on surgically resected renal masses--benign or malignant? Urology 2013; 81: 707-13. DOI: https://doi.org/10.1016/j.urology.2013.01.009
Israel GM, Bosniak MA. An update of the Bosniak renal cyst classification system. Urology 2005; 66: 484–8. DOI: https://doi.org/10.1016/j.urology.2005.04.003
Jonisch AI, Rubinowitz AN, Mutalik PG, Israel GM. Can high-attenuation renal cysts be differentiated from renal cell carcinomaat unenhanced CT? Radiology 2007; 243: 445–50. DOI: https://doi.org/10.1148/radiol.2432060559
Silverman SG, Israel GM, Herts BR, Richie JP. Management of the incidental renal mass. Radiology 2008; 249:16–31. DOI: https://doi.org/10.1148/radiol.2491070783
Willatt J, Francis IR. Imaging and management of the incidentally discovered renal mass. Cancer Imaging 2009; 9 (Spec No A): S30–7. DOI: https://doi.org/10.1102/1470-7330.2009.9008
Schieda N, Vakili M, Dilauro M, Hodgdon T, Flood TA, Shabana WM. Solid renal cell carcinoma measuring water attenuation (-10 to 20 HU) on unenhanced CT. Am J Roentgenol 2015: 1215-21. DOI: https://doi.org/10.2214/AJR.15.14554
Pooler BD, Pickhardt PJ, O’Connor SD, Bruce RJ, Patel SR, Nakada SY. Renal cell carcinoma: Attenuation values on unenhanced CT. Am J Roentgenol 2012; 198: 1115-20. DOI: https://doi.org/10.2214/AJR.11.7587
Sheir KZ, El-Azab M, Mosbah A, El-Baz M, Shaaban AA. Differentiation of renal cell carcinoma subtypes by multi slice computerized tomography. J Urol 2005; 174: 451-5. DOI: https://doi.org/10.1097/01.ju.0000165341.08396.a9
Reuter VE, Presti Jr JC. Contemporary approach to the classification of renal epithelial tumors. Semin Oncol 2000; 27: 124.
Fujimoto H, Wakao F, Moriyama N, Tobisu K, Sakamoto M, Kakizoe T. Alveolar architecture of clear cell renal carcinomas ( DOI: https://doi.org/10.1093/jjco/29.4.198
Abdulla C, Kalra MK, Saini S, Maher MM, Ahmad A, Halpern E, et al. Pseudoenhancement of simulated renal cysts in a phantom using different multidetector CT scanners. AJR Am J Roentgenol 2002; 179: 1473-6. DOI: https://doi.org/10.2214/ajr.179.6.1791473
Wang ZJ, Coakley FV, Fu Y, Joe BN, Prevrhal S, Landeras LA, et al. Renal cyst pseudoenhancement at multidetector CT: what are the effects of number of detectors and peak tube voltage? Radiology 2008; 248: 910-6. DOI: https://doi.org/10.1148/radiol.2482071583
Pickhardt PJ, Kim DH, Meiners RJ, Wyatt KS, Hanson ME, Barlow DS, et al. Colorectal and extracolonic cancers detected at screening CT colonography in 10,286 asymptomatic adults. Radiology 2010; 255: 83-8. DOI: https://doi.org/10.1148/radiol.09090939
Song C, Min GE, Song K, Kim JK, Hong B, Kim CS, et al. Differential diagnosis of complex cystic renal mass using multiphase computerized tomography. J Urol 2009; 181: 2446-50. DOI: https://doi.org/10.1016/j.juro.2009.01.111
Zhang J, Lefkowitz RA, Ishill NM, Wang L, Moskowitz CS, Russo P, et al. Solid renal cortical tumors: differentiation with CT. Radiology 2007; 244: 495-504. DOI: https://doi.org/10.1148/radiol.2442060927
O’Connor SD, Pickhardt PJ, Kim DH, Oliva MR, Silverman SG. Incidental renal masses at unenhanced CT: prevalence and analysis of features for guiding management. Am J Roentgenol 2011; 197: 139–45. DOI: https://doi.org/10.2214/AJR.10.5920
Downloads
Published
How to Cite
Issue
Section
License
The Journal of Southeast Asian Medical Research will hold the copyright to all published articles. The publisher's production department handles copyright forms once a manuscript is accepted and scheduled for publication.
