Myxoid Liposarcoma


Myxoid liposarcomas (MLS) are malignant tumours that usually occur as a large painless mass and occur commonly in the extremities, particularly the thigh.  This tumour classification accounts for 15-20% of liposarcomas and represents 5% of all soft tissue sarcomas in adults. 

95% of cases have a t(12;16)(q13;p11) rearrangement resulting in the fusion of the 5’FUS to the 3’DDIT3. 5% of cases can have a t(12;22)(q13;q12) resulting in a fusion of EWSR1 and DDIT3. The different fusions are not known to be associated with a difference in histological grade or clinical outcome.


  • Completed CGL Cytogenetics Solid Tumour Testing requisition form
  • FFPE Tumour specimen (see Specimen GuidelinesCytogenetics FISH FFPE test type)
    • An H&E stained slide with the tumour region circled, and the estimated % tumour content written in the Tumour Content field of the requisition.  NOTE: A minimum of 10% tumour and at least 200 nuclei is required.
    • Specimen block and/or at least one unstained slide for each probe requested.


Results are reported within fourteen days from receipt of specimen and completed requisition form.  


  • Specimens are reported as Positive for a DDIT3 rearrangement or Negative for a DDIT3 rearrangement.
  • DDIT3 rearrangements are identified in almost all myxoid liposarcomas


FISH analysis is performed on the provided paraffin embedded tissue using the DDIT3 (12q13) dual-colour, break-apart probe (Vysis).


  1. Narendra  et al. Diagn Mol Pathol (2011) PMID: 22089349  
  2. Downs-Kelly et al. Am J Surg Pathol.  (2008)  PMID: 18162764
  3. Bode-Lesniewska et al. Genes Chromosomes Cancer  (2007) PMID: 17647282