title: [Myxoid liposarcoma. MRI imaging].
abstract: OBJECTIVE
  Myxoid liposarcoma is the most common type of liposarcoma (approximately 40 to 50% of all liposarcomas). The main tissue component is a myxoid matrix present primarily in extracellular compartments; proliferating lipoblasts account for less 10% of the tumor: MRI appearances are not typical for lipomatous tumor. Nevertheless histological features may permit understanding MRI findings and identifying patients with myxoid liposarcoma.
  
  
  METHODS
  Clinical history and radiologic images of 7 patients with histologically verified myxoid liposarcoma were retrospectively studied. In all patients the tumor presented in a lower extremity as a painless, slowly growing mass. MR images were available for review in all cases (T1- and T2-weighted images); in addition fat-suppression before and after gadolinium enhancement were assessed with T1-weighted sequences.
  
  
  RESULTS
  MRI examination revealed an "encapsulated" tumor, non infiltrating and septated. On T1-weighted sequences all the lesions show lacy, amorphous and linear foci of high signal within a low signal of the tumor due to the predominance of a myxoid matrix. The high sensitivity of MRI demonstrates the presence of small areas of high signal and fat-suppression technique is valuable for characterizing soft-tissue tumors: suppression of high signal intensity on fat-saturated T1-weighted images indicates the presence of fatty tissue components.
  
  
  CONCLUSIONS
  Clinical correlation with MRI appearances on T1-weighted sequences (in addition to fat-suppression technique) may suggest the possibility of myxoid liposarcoma.
authors.affiliation: Service de Radiologie, Hôpital d'Instruction des Armées du Val-de-Grâce, Paris.
authors.forename: D
authors.initials: D
authors.lastname: Soulié
authors.forename: B
authors.initials: B
authors.lastname: Boyer
authors.forename: J
authors.initials: J
authors.lastname: Lescop
authors.forename: A
authors.initials: A
authors.lastname: Pujol
authors.forename: G
authors.initials: G
authors.lastname: Le Friant
authors.forename: Y S
authors.initials: YS
authors.lastname: Cordoliani
mesh_terms: D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007866:Leg; D018208:Liposarcoma, Myxoid / Q000175:diagnosis* / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012983:Soft Tissue Neoplasms / Q000175:diagnosis* / Q000473:pathology
vernacular_title: Liposarcome myxoïde. Aspects en IRM.