Fact-sheet: Retroperitoneal liposarcoma
Updated on 10/07/2017 at 6:42 AM
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Definition
Liposarcoma is one of the most common types of soft-tissue sarcoma.
Primary malignant tumor arising from adipocytic cells
Clinical features
Mass of variable tenderness depending on location, with variable growth rate.
Predilection for the lower limb, then the retroperitoneum.
CT
Well-differentiated liposarcoma usually contains more than 75% fat cells. The lesion has well-defined margins, negative density (below -60 Hounsfield units), and thick septa or even intralesional nodules.
MRI
T1 and T2 hyperintense signal,
hypointense on fat-suppressed sequences, reflecting the fatty component.
Look for signs of malignancy:
- size >6cm
- thick septa (2mm)
- nodular and soft-tissue elements with contrast enhancement.
Guides the area to be biopsied.
Myxoid liposarcoma appears T1 hypointense.
Pleomorphic liposarcoma is nonspecific.
Management
Biopsy after multidisciplinary tumor board discussion +++, MRI-guided, looking for the nonfatty component.
Surgical excision.
Classification
The WHO classification distinguishes four different groups of liposarcomas: (1) well differentiated (2) dedifferentiated (3) myxoid (4) pleomorphic
