Renal oncocytoma: Is URO‐CT useful in histological diagnosis?

  • João Almeida Dores Serviço de Urologia, Hospital Prof. Doutor Fernando Fonseca, Amadora, Portugal
  • Peter Kronenberg Serviço de Urologia, Hospital Prof. Doutor Fernando Fonseca, Amadora, Portugal
  • Pedro Bargão Santos Serviço de Urologia, Hospital Prof. Doutor Fernando Fonseca, Amadora, Portugal
  • Sérgio Ferreira Serviço de Imagiologia, Hospital Prof. Doutor Fernando Fonseca, Amadora, Portugal
  • Francisco Carrasquinho Gomes Serviço de Urologia, Hospital Prof. Doutor Fernando Fonseca, Amadora, Portugal


Over the past few years, the increasing use of cross‐sectional imaging, including ultrasound and computed tomography imaging, resulted in an increase incidental diagnosis of renal tumors, especially small renal masses (<4cm). The knowledge that 30% of these masses may be benign, including oncocytomas led to the investigation for more effective methods of diagnosis in order to avoid overtreatment situations.
The authors decided to analyse and compare contrast enhancement patterns of oncocytomas and clear‐cell renal cell carcinoma (ccRCC) to predict histology.
Material and methods
Between 2004‐2015 we retrospectively identified 32 patients with either histological confirmation of renal oncocytoma (N=16) or ccRCC (N=16) who underwent percutaneous biopsy, total or partial nephrectomy. The relative attenuation of solid renal lesions and normal renal cortex was determined in the unenhanced and nephrographic phase. Statistical comparison was carried out by Mann‐Withney test.
The oncocytomas and cc‐RCC average size was 3.7cm [1.8 to 14] and 3.5cm [1.9 to 8.4], respectively. The average attenuation in the unenhanced phase was 33HU and 32HU, respectively. In nephrographic phase, the average contrast enhancement was 47.5 and 47.4H, respectively. In nephrographic phase, the attenuation difference between the oncocytomas and normal renal cortex was 43.5HU and the attenuation difference between the cc‐RCC and normal renal cortex was 59.7HU. These results were statistically significant (p<0.05).
In the nephrographic phase, URO‐CT reveals that oncocytomas have greater isodensity to the normal renal cortex compared to cc‐RCC. This finding can help us to determine which lesions we should biopsy or not.


1. Lane BR, Tolbert CM, Kiesinger CB. Growth kinetics and active surveillance for small renal masses. Curr Opin Urol. 2012;22:353-9.

2. Volpe A, Panzarella T, Rendon RA, Haider MA, Kondylis FI, Jewett MA. The natural history of incidentally detected small renal masses. Cancer. 2004;100:738-45.

3. Frank T, Blute ML, Cheville JC, Lohse CM, Weaver AL, Zincke H. Solid renal tumors: An analysis of pathological features related to tumor size. J Urol. 2003;170:2217-20.

4. Soga N, Nishikawa K, Takaki H, Yamada Y, Arima K, Hayashi N, et al. Low incidence of benign lesions in resected suspicious renal masses greater than 2 cm: Single-center experience from Japan. Int J Urol. 2012;19:729-34.

5. Schlomer B, Figenshau RS, Yan Y, Venkatesh R, Bhayani SB. Pathological features of renal neoplasms classified by size and symptomatology. J Urol. 2006;176:1317-20.

6. Duchene DA, Lotan Y, Cadeddu JA, Sagalowsky AI, Koeneman KS. Histopathology of surgically managed renal tumors: Analysis of a contemporary series. Urology. 2003;62:827-30.

7. Violette P, Abourbih S, Szymanski KM, Tanguay S, Aprikian A, Matthews K, et al. Solitary solid renal mass: Can we predict malignancy? BJU Int. 2012;110:548-52.

8. Ehsani L, Seth R, Bacopulos S, Seth A, Osunkoya AO. BCA2 is differentially expressed in renal oncocytoma an analysis of 158 renal neoplasms. Tumour Biol. 2013;34(2):787-91.

9. Perez-Ordonez B, Hamed G, Campbell S, Erlandson RA, Russo P, Gaudin PB, et al. Renal oncocytoma: A clinicopathologic study of 70 cases. Am J Surg Pathol. 1997;21(8):871-83.

10. Garant M, Bonaldi VM, Taourel P, Pinsky MF, Bret PM. Enhancement patterns of renal masses during multiphase helical CT acquisitions. Abdom Imaging. 1998;23(4):431-6.

11. Neisius D, Braedel HU, Schindler E, Hoene E, Alloussi S. Computed tomographic and angiographic findings in renal oncocytoma. Br J Radiol. 1988;61(731):1019-25.

12. Millet I, Doyon FC, Hoa D, Thuret R, Merigeaud S, Serre I, et al. Characterization of small solid renal lesions: Can benign and malignant tumors be differentiated with CT? AJR Am J Roentgenol. 2011;197(4):887-96.

13. Cornelis F, Tricaud E, Lasserre AS, Petitpierre F, Bernhard JC, le Bras Y, et al. Routinely performed multiparametric magnetic resonance imaging helps to differentiate common subtypes of renal tumours. Eur Radiol. 2014;24(5):1068-80.

14. Wu J, Zhu Q, Zhu W, Chen W, Wang S. Comparative study of CT appearances in renal oncocytoma and chromophobe renal cell carcinoma. Acta Radiol. 2015.

15. Zhang J, Lefkowitz RA, Ishill NM, Wang L, Moskowitz CS, Russo P, et al. Solid renal cortical tumors: Differentiation with CT. Radiology. 2007 Aug;244(2):494-504.

16. Gakis G, Kramer U, Schilling D, Kruck S, Stenzl A, Schlemmer HP. Small renal oncocytomas: Differentiation with multiphase CT. Eur J Radiol. 2011 Nov;80(2):274-8.

17. Choudhary S, Rajesh A, Mayer NJ, Mulcahy KA, Haroon A. Renal oncocytoma: CT features cannot reliably distinguish oncocytoma from other renal neoplasms. Clin Radiol. 2009 May;64(5):517-22.

18. EAU guidelines-Renal cell carcinoma 2015.

19. Richard PO, Jewett MA, Bhatt JR, Kachura JR, Evans AJ, Zlotta AR, et al. Tumor biopsy for small renal masses: A
single-center 13-year experience. Eur Urol. 2015 Dec;68(6): 1007-13.
How to Cite
ALMEIDA DORES, João et al. Renal oncocytoma: Is URO‐CT useful in histological diagnosis?. Acta Urológica Portuguesa, [S.l.], v. 33, n. 3, p. 98-103, apr. 2017. ISSN 2387-0419. Available at: <>. Date accessed: 28 apr. 2017.
Original Article