title: MR differentiation of low-grade chondrosarcoma from enchondroma.
abstract: OBJECTIVE
  To evaluate magnetic resonance (MR) imaging for the discrimination between low-grade chondrosarcoma and enchondroma.
  
  
  METHODS
  MR images of 34 patients who were confirmed with low-grade chondrosarcoma or enchondroma were retrospectively reviewed. After review of medical records, MR findings in 18 patients with low-grade chondrosarcoma and 16 patients with enchondroma were compared. MR images were retrospectively reviewed for the lesion location (central or eccentric; epiphysis, metaphysic, or diaphysis), margin, contour, mineralized matrix, endosteal scalloping, cortical expansion, cortical destruction, soft tissue mass formation, and periosteal reaction. Signal intensity, the patterns of contrast enhancement (unilocular or multilobular), soft tissue mass, and adjacent abnormal bone marrow and soft tissue signal were also reviewed. Statistical analysis was performed with chi-square test.
  
  
  RESULTS
  The patients with low-grade chondrosarcoma had a significantly higher incidence of MR findings (P<.05): predominantly intermediate signal on T1-weighted images [72% (13/18) in low-grade chondrosarcoma vs. 25% (4/16) in enchondroma], multilocular appearance on contrast-enhanced T1-weighted images [83% (15/18) vs. 44% (7/16)], cortical destruction [33% (6/18) vs. 0% (0/16)], a soft tissue mass [28% (5/18) vs. 0% (0/16)], adjacent bone marrow and soft tissue abnormal signal [22% (4/18) vs. 0% (0/16)], and an involvement of the epiphysis or flat bone [56% (10/18) vs. 19% (3/16)].
  
  
  CONCLUSIONS
  MR imaging shows helpful features for differentiating low-grade chondrosarcoma from enchondroma.
authors.affiliation: Department of Radiology, Chungnam National University Hospital, Daejeon 301-721, Korea.
authors.forename: Bo-Bae
authors.initials: BB
authors.lastname: Choi
authors.forename: Won-Hee
authors.initials: WH
authors.lastname: Jee
authors.forename: Hee-Jung
authors.initials: HJ
authors.lastname: Sunwoo
authors.forename: Jae-Hyun
authors.initials: JH
authors.lastname: Cho
authors.forename: Jee-Young
authors.initials: JY
authors.lastname: Kim
authors.forename: Kyung-Ah
authors.initials: KA
authors.lastname: Chun
authors.forename: Suk-Joo
authors.initials: SJ
authors.lastname: Hong
authors.forename: Hye Won
authors.initials: HW
authors.lastname: Chung
authors.forename: Mi-Sook
authors.initials: MS
authors.lastname: Sung
authors.forename: Yeon-Soo
authors.initials: YS
authors.lastname: Lee
authors.forename: Yang-Guk
authors.initials: YG
authors.lastname: Chung
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000473:pathology*; D002648:Child; D002812:Chondroma / Q000473:pathology*; D002813:Chondrosarcoma / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012983:Soft Tissue Neoplasms / Q000473:pathology*; D055815:Young Adult