+ 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
- Sites: subcutaneous tissue (axial or appendicular), visceral (spleen and liver), and skeletal
- Liposarcomas can infiltrate into veins, lymphatics, and underlying muscle
+ Biologic Behavior
Aggressive and locally invasive ± metastasis to lungs, liver, and bone
+ 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