MRI features of extraskeletal myxoid chondrosarcoma.
OBJECTIVE
To describe the MRI features of extraskeletal myxoid chondrosarcoma in comparison with clinicopathologic findings.


METHODS
The study comprised 12 male subjects and seven female subjects with a mean age of 53 years (range 16-76 years). MRI findings, evaluated by two radiologists with agreement by consensus, were compared for histopathologic features.


RESULTS
The tumor size ranged from 2.0 cm to 20.0 cm (mean 8.9 cm). Fusion gene transcripts could be detected in 13 (68%) of the 19 cases: EWS-CHN in nine cases, TAF2N-CHN in three, and TFG-TCH in one. There were six fusion-negative cases. Signal characteristics on T1-weighted and T2-weighted MR images were non-specific with regard to each cytogenetic variant. Peripheral enhancement was seen more frequently in tumors with the EWS-CHN variant than in those with other cytogenetic variants. The characteristic pattern of enhancement corresponded to the presence of fibrous septa and peripheral areas of high cellularity within lobules, by correlation with pathologic findings. All cases with TAF2N-CHN or TFG-TCH variants showed invasion of extracompartmental structure, bone, or vessels.


CONCLUSIONS
Extraskeletal myxoid chondrosarcoma is an uncommon soft-tissue malignancy that may be recognized by MRI features of multi-lobular soft-tissue mass often invading extracompartmental, bony, and vascular structures.
Tateishi
Ukihide
U
Division of Diagnostic Radiology, National Cancer Center Hospital, 5-1-1, Tsukiji, Chuo-Ku, 104-0045 Tokyo, Japan. utateish@ncc.go.jp
Hasegawa
Tadashi
T
Nojima
Takayuki
T
Takegami
Tsutomu
T
Arai
Yasuaki
Y
D000293:Adolescent; D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000473:pathology; D002813:Chondrosarcoma / Q000473:pathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012983:Soft Tissue Neoplasms / Q000473:pathology*