Computerized tomography characteristics that differentiate angiomyolipomas from liposarcomas in the perinephric space.
OBJECTIVE
We performed a retrospective study to determine computerized tomography (CT) findings associated with perinephric angiomyolipomas or perinephric liposarcomas.


METHODS
During the last 7 years 6 patients with perinephric angiomyolipoma and 12 with perinephric liposarcoma were seen at our hospital. Two radiologists who were blinded to the pathological diagnosis retrospectively evaluated the CT characteristics of perinephric angiomyolipoma and perinephric liposarcoma. The relationship of each CT characteristic with tumor type was compared using Fisher's exact test.


RESULTS
The CT characteristics of perinephric angiomyolipoma were intratumoral linear vascularity (p = 0.001), aneurysmal dilatation (p = 0.025), bridging vessel sign (p = 0.005), hematoma (p = 0.025), beak sign (p = 0.001) and discrete intrarenal fatty tumors (p = 0.025). The CT characteristic of perinephric liposarcoma was a nonfatty soft tissue mass (p = 0.005). There was no significant difference in the presence of calcifications in both groups.


CONCLUSIONS
This retrospective study suggests that analysis of CT characteristics (linear vascularity, aneurysmal dilatation, bridging vessel sign, hematoma, beak sign and discrete intrarenal fatty tumors) may help to differentiate perinephric angiomyolipoma from perinephric liposarcoma.
Wang
Li-Jen
LJ
Department of Diagnostic Radiology, Chang Gung Memorial Hospital and Biostatistics Center, Chang Gung University, Taipei, Taiwan.
Wong
Yon-Cheong
YC
Chen
Chi-Jen
CJ
See
Lai-Chu
LC
D000328:Adult; D018207:Angiomyolipoma / Q000000981:diagnostic imaging*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging*; D008080:Liposarcoma / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011856:Radiographic Image Enhancement; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed