J Korean Soc Radiol.  2016 Sep;75(3):227-231. 10.3348/jksr.2016.75.3.227.

Imaging Findings of Perirenal Epithelioid Angiomyolipoma Mimicking a Malignant Retroperitoneal Tumor: A Case Report with Imaging Findings

• Kim JY
• Woo JY
• Shin MK
• Lee Y
• Hwang JY
• Kim HY
• Park SB

• KMID: 2349331
• DOI: http://doi.org/10.3348/jksr.2016.75.3.227

Abstract

Epithelioid angiomyolipoma (EAML) is an uncommon, variant type of angiomyolipoma with a possibility of metastatic transformation and distant spread. Angiomyolipomas, including epithelioid variant type, are mostly renal in origin. EAML originating from extrarenal location is very rare and imaging findings are not well described. Herein, we reported a very rare case of EAML arising from the perirenal space that mimicked a malignant retroperitoneal tumor, in a 39-year-old female.

MeSH Terms

Adult
Angiomyolipoma*
Female
Humans
Retroperitoneal Neoplasms
Retroperitoneal Space
Tomography, X-Ray Computed

Figure

• 

  Fig. 1 Retroperitoneal epithelioid angiomyolipoma in a 39-year-old female with no associated symptom. A. Coronal CT image reveals location of the mass in relation to the left kidney. Normal left adrenal gland (arrow) and superior displacement of the pancreas (arrowhead) are noted. B. Unenhanced CT image shows large, high-density mass abutting to the left kidney with internal low attenuated lesions. C-E. Mass shows rapid contrast enhancement with slow wash-out on 30 second delayed (C), 75 second delayed (D), and 5 min delayed (E) phase images. F. US image demonstrates heterogeneous echoic mass with internal cystic areas and the mass is separated from the left kidney by thin hyperechoic fat (arrow). G, H. Microscopically, the specimen is composed of dysmorphic thick walled blood vessels, islands of mature adipose cells and predominant population of large epithelioid cells with eosinophilic cytoplasm (G, hematoxylin and eosin staining, original magnification × 40) and epithelioid cells reveals strong and diffuse HMB-45 immunopositivity (H, HMB-45 immunohistochemical staining, original magnification × 400). HMB = human melanoma black, US = ultrasonography

Reference

1. Lau SK, Marchevsky AM, McKenna RJ Jr, Luthringer DJ. Malignant monotypic epithelioid angiomyolipoma of the retroperitoneum. Int J Surg Pathol. 2003; 11:223–228.

2. Gupta C, Malani AK, Gupta V, Singh J, Ammar H. Metastatic retroperitoneal epithelioid angiomyolipoma. J Clin Pathol. 2007; 60:428–431.

3. Yokoo H, Isoda K, Nakazato Y, Nakayama Y, Suzuki Y, Nakamura T, et al. Retroperitoneal epithelioid angiomyolipoma leading to fatal outcome. Pathol Int. 2000; 50:649–654.

4. Wen J, Li HZ, Ji ZG, Mao QZ, Shi BB, Yan WG. Renal epithelioid angiomyolipoma without obvious local progress in 10 years: a case report and literature review. Ir J Med Sci. 2011; 180:557–560.

5. Ameurtesse H, Chbani L, Bennani A, Toughrai I, Beggui N, Kamaoui I, et al. Primary perivascular epithelioid cell tumor of the liver: new case report and literature review. Diagn Pathol. 2014; 9:149.

6. Kanazawa A, Fujii S, Godai TI, Ishibe A, Oshima T, Fukushima T, et al. Perivascular epithelioid cell tumor of the rectum: report of a case and review of the literature. World J Surg Oncol. 2014; 12:12.

7. Surabhi VR, Menias C, Prasad SR, Patel AH, Nagar A, Dalrymple NC. Neoplastic and non-neoplastic proliferative disorders of the perirenal space: cross-sectional imaging findings. Radiographics. 2008; 28:1005–1017.

8. Choi SY, Sung DJ, Han NY, Park BJ, Kim MJ, Sim KC, et al. Renal malakoplakia with wide extension into the retroperitoneum: a case report. J Korean Soc Radiol. 2015; 73:62–65.

9. Cui L, Zhang JG, Hu XY, Fang XM, Lerner A, Yao XJ, et al. CT imaging and histopathological features of renal epithelioid angiomyolipomas. Clin Radiol. 2012; 67:e77–e82.

10. Bharwani N, Christmas TJ, Jameson C, Moat N, Sohaib SA. Epithelioid angiomyolipoma: imaging appearances. Br J Radiol. 2009; 82:e249–e252.