title: Incomplete paresis of the sciatic nerve due to massive atypical lipoma of the pelvis: a case report.
abstract: BACKGROUND
  Liposarcomas are classified into four subtypes, with different malignancy potential and characteristic imaging appearances. Well-differentiated liposarcomas have imaging characteristics similar to those of benign lipomas, however they can be usually distinguished from lipomas because of the larger size and broader fibrous septa, with a more nodular appearance.
  
  
  METHODS
  This paper presents a case of atypical lipoma (well-differentiated liposarcoma) of the pelvis, leading to partial involvement of the sciatic nerve. In our case, computed tomography (CT) showed a low-density lesion. In magnetic resonance imaging (MRI), T1 and T2-weighted sequences revealed a fatty appearance with signal loss on fat saturation pulse sequences.
  
  
  CONCLUSIONS
  The lesion was successfully resected and no other similar lesions have been found within one year of follow-up.
authors.affiliation: Friedrich Schiller University Jena, Erlanger Allee 101, D-07747 Jena, Germany. andreas.hansch@med.uni-jena.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Hansch
authors.forename: Mieczyslaw
authors.initials: M
authors.lastname: Gajda
authors.forename: Joachim
authors.initials: J
authors.lastname: Boettcher
authors.forename: Alexander
authors.initials: A
authors.lastname: Pfeil
authors.forename: Werner A
authors.initials: WA
authors.lastname: Kaiser