Infiltrative Lipoma In A Canine Stifle Joint

A 10-year-old-Lhasa apso was presented with a large mass in the stifle area causing lameness. Radiographs revealed osteolysis and exostoses. Biopsies of the mass on separate occasions demonstrated an infiltrative lipoma involving joint capsule, periosteum, and bone. The tumor had grown slowly and was only mildly painful. Although this has been reported rarely, clinicians should be aware of the possibility of bone and joint capsule invasion with infiltrative lipomas.