Purpose
To investigate CT features that distinguish exophytic angiomyolipoma from retroperitoneal liposarcoma accurately.
Methods and Materials
17 cases of exophytic angiomyolipoma and 7 cases of retroperitoneal liposarcoma proved by pathology and/or other items were analyzed retrospectively with their MDCT images. The following CT features associated with tumor type were compared using Fisher’s exact test: (1) renal parenchymal defect at the site of tumor contact, (2) kidney displacement anteriorly, (3) enlarged vessel, (4) supplyment of renal artery branches, (5) tumoral vessel through the renal parenchyma, (6) calcification, (7) non-fat-attenuating enhanced intratumoral nodules, (8) hemorrhage, and (9) associated angiomyolipoma.
Results
The CT features only or mainly associated with exophytic angiomyolipoma were renal parenchymal defect at the site of tumor contact, enlarged vessel, supplyment of renal artery branches and tumoral vessel through the renal parenchyma (all P<0.01) ; while which associated with retroperitoneal liposarcoma were kidney displacement anteriorly and non-fat-attenuating enhanced intratumoral nodules (all P<0.01). There was no significant difference in the presence of calcification, hemorrhage and associated angiomyolipoma in both groups (P>0.05).
Conclusion
In the evaluation of a large fat-containing perinephric mass at CT, the presence of renal parenchymal defect at the site of tumor contact, enlarged vessel, supplyment of renal artery branches and tumoral vessel through the renal parenchyma suggests the diagnosis of exophytic angiomyolipoma, whereas the presence of kidney displacement anteriorly and non-fat-attenuating enhanced intratumoral nodules suggests retroperitoneal liposarcoma.
References
[1] Nelson CP, Sanda MG. Contemporary diagnosis and management of renal angiomyolipoma. J Urol, 2002, 168(4 Pt 1):1315-1325.[2]Yip SK, Tan PH, Cheng WS, et al. Surgical management of angiomyolipoma: nephron-sparing surgery for symptomatic tumour. Scand J Urol Nephrol, 2000, 34(1):32-35.[3]Karanikas I, Liakakos T, Koundourakis S, et al. Surgical management of primary retroperitoneal liposarcomas. Acta Chir Belg, 1993, 93(4):177-180.[4]Craig WD, Fanburg-Smith JC, Henry LR, et al. Fat-containing lesions of the retroperitoneum: radiologic-pathologic correlation. Radiographics, 2009, 29(1):261-290.[5]Wang LJ, Wong YC, Chen CJ, et al. Computerized tomography characteristics...
Personal Information
Qiushi WANG，Hui LIU，Changhong LIANGDepartment of Radiology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, ChinaCorresponding author:Changhong LIANG
