Imaging findings of solitary fibrous tumor in the abdomen and pelvis.
OBJECTIVE
The purpose of this study was to investigate the imaging characteristics of solitary fibrous tumor (SFT) in the abdomen and pelvis.


METHODS
Nine cases of SFT confirmed by surgery and pathology were retrospectively analyzed in terms of computed tomography (CT, eight cases) and magnetic resonance imaging (MRI, one case).


RESULTS
SFT were located in the retroperitoneum (4/9), abdominal cavity (1/9), pelvis (4/9). Eight cases were single (8/9) and one case (1/9) with three tumors. The average tumor size of 11 lesions was 9.7 cm (4.7-20 cm). Nine tumors were round or ovoid, and two lesions were irregular. The CT value of the plain scans ranged from 33 to 43 Hounsfield units (HU, mean 37.6 HU) in five cases. Arterial-phase CT found solid parts demonstrate avid enhancement (eight cases) and five of them presented with multiple circuitous vessels along the periphery with a CT value of 68-89 HU (mean 76.6 HU). In the venous and delayed phases, enhancement was strengthened progressively. The CT values at venous (eight cases) and delayed phases (five cases) were 108-115 and 112-123 HU respectively, with averages of 109.8 and 114.8 HU. Patch or nodular no-enhanced areas were observed in eight cases during the enhanced phases. One case showed isointensity on T1-weighted images and high signal intensity on T2-weighted images accompanied by linear or curvilinear hypointense lines. Intense enhancements along with linear no-enhancement areas are seen in the arterial and venous phases.


CONCLUSIONS
The possibility of SFT should be considered when a single or multiple masses with sharp border, inhomogeneous density or signal are detected, especially, with inhomogeneous intense enhancement in the arterial phase being maintained in the venous and delayed phases.
Department of Radiology, Su Bei People's Hospital of Yangzhou University, No. 98, Nan Tong West Road, Yangzhou, 225009, Jiangsu, People's Republic of China, tongtiantian2001@163.com.
T-T
TT
Tian
Jing-Tao
JT
Wu
X-H
XH
Hu
G-M
GM
Yang
J
J
Sun
W-X
WX
Chen
X-C
XC
Tian
D034841:Abdominal Cavity / Q000000981:diagnostic imaging / Q000473:pathology; D000008:Abdominal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D000328:Adult; D000368:Aged; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007472:Iohexol / Q000031:analogs & derivatives; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010386:Pelvic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D010388:Pelvis / Q000000981:diagnostic imaging / Q000473:pathology; D012189:Retrospective Studies; D054364:Solitary Fibrous Tumors / Q000175:diagnosis*; D014057:Tomography, X-Ray Computed / Q000379:methods; D055815:Young Adult
D003287:Contrast Media; D007472:Iohexol; C038192:iopromide; D019786:Gadolinium DTPA