Synovial sarcoma: frequency of nonaggressive MR characteristics.
OBJECTIVE
Our objective was to examine the MR characteristics of synovial sarcoma and determine the frequency of a nonaggressive imaging appearance.


METHODS
Fifteen patients with histologically confirmed cases of synovial sarcoma and prior MR examinations were seen. Retrospective analysis of imaging features included assessment of size, margins, homogeneity, internal architecture, T1- and T2-weighted signal intensities, and bone invasion.


RESULTS
Five of 15 patients (33%) had well circumscribed, homogeneous lesions with a mean length of 4.8 cm. The T1-weighted signal intensity was either isointense to muscle or greater in signal intensity than muscle. The T2-weighted images demonstrated signal intensity equal to or greater than fat. The remaining 10 lesions were larger (mean length of 11.3 cm) with mild to complex levels of inhomogeneity and margins that varied from well circumscribed to infiltrating.


CONCLUSIONS
There are two sets of MR features seen with synovial sarcoma. Small lesions of -5 cm can demonstrate a nonaggressive appearance with well circumscribed margins and homogeneous signal intensity. These tumors could be confused with benign lesions, resulting in inappropriate surgical intervention like excisional biopsies through transverse incisions. This would make future surgery more difficult. Larger lesions tend to be more heterogeneous in signal intensity.
Blacksin
M F
MF
Department of Radiology, University of Medicine and Dentistry of New Jersey, Newark 07103, USA.
Siegel
J R
JR
Benevenia
J
J
Aisner
S C
SC
D000273:Adipose Tissue / Q000473:pathology; D000293:Adolescent; D000328:Adult; D000368:Aged; D001365:Axilla / Q000473:pathology; D001859:Bone Neoplasms / Q000473:pathology; D002648:Child; D003287:Contrast Media; D005260:Female; D005534:Foot Diseases / Q000175:diagnosis / Q000473:pathology / Q000601:surgery; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007592:Joint Diseases / Q000175:diagnosis / Q000473:pathology / Q000601:surgery; D007719:Knee Joint / Q000473:pathology; D007866:Leg; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology; D009361:Neoplasm Invasiveness; D010386:Pelvic Neoplasms / Q000473:pathology; D012189:Retrospective Studies; D013584:Sarcoma, Synovial / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery; D013848:Thigh / Q000473:pathology
D003287:Contrast Media