General Considerations

•uncommon malignant tumor of adipose tissue

•no breed or sex predilection

•liposarcoma does not arise from malignant transformation of lipoma

•liposarcoma associated with type-C virus particles in cats (i.e., retroviral infection) and reported secondary to glass foreign body in a dog

•biologic behaviour: aggressive and locally invasive ± metastasis to lungs, liver, and bone

•sites: subcutaneous tissue (axial or appendicular), visceral (spleen and liver), and skeletal

•liposarcomas can infiltrate into veins, lymphatics, and underlying muscle

•prognosis: guarded to good

•28% (12/43) local tumor recurrence with 83% (10/12) of these occurring in dogs with marginal excision

•metastatic rate < 10%

•MST 694 days

•surgical dose is the only prognostic factor for survival with MST for incisional biopsy 183 days, 649 days for marginal excision, and 1,188 days for wide excision

•however, MST for tumor size < 4 cm is 961 days and ≥ 4 cm is 612 days

•metastatic predictors in humans: histologic grade and tumor size

See Soft Tissue Sarcoma for more information