Liposarcomas are a heterogenous group of soft tissue sarcomas. The common histological cell is the lipoblast (signet ring cell). The plain radiograph shows the large lesion with increased soft tissue density but no overlying bone changes. MRI shows a large lesion in the posterior thigh that is heterogeneous, dark on T1 and bright on T2). Multiple different sub-types of liposarcoma exist including well-differentiated, round cell, myxoid, etc. Treatment of liposarcomas includes radiotherapy and surgical excision.
Kilpatrick et al evaluated 95 patients retrospectively and found on multivariate analysis that age over 45years, greater than 25% round cell differentiation, and tumor necrosis were all poor prognosticators in liposarcoma.
Sundaram et al evaluated the MRI characteristics of myxoid liposarcomas (the most common subtype of liposarcoma). They found that myxoid liposarcomas contain less than 10% mature fat accounting for their T1 signaling characteristics (dark on T1).
Schwartz et al present a case report regarding liposarcoma of the extremities and provide a valuable review of the imaging characteristics, treatment options, and local and distant recurrence outcomes of liposarcomas.
Kilpatrick SE, Doyon J, Choong PF, Sim FH, Nascimento AG. The clinicopathologic spectrum of myxoid and round cell liposarcoma: A study of 95 cases. Cancer 1996;77:1450-1458
PMID:8608528 (Link to Abstract)
Sundaram M, Baran G, Merenda G, McDonald DJ. Myxoid liprosarcoma: Magnetic resonance imaging appearances with clinical and histological correlation. Skeletal Radiol 1990;19:359-362
PMID:2377902 (Link to Abstract)
Schwartz HS, Weiss SW, Sim FH, Beabout JW. Liposarcoma of the soft tissues. Orthopedics 1987;10:1065-1068
PMID:3615295 (Link to Abstract)