Case Report: Long-term outcomes after surgery for spinal infiltrative lipoma in two dogs

An eight-year-old male intact shepherd mixed breed dog (case 1) and a 6-month-old intact female Picardy sheepdog (case 2) were referred to a Veterinary Teaching Hospital with the diagnosis of infiltrative lipoma causing spinal cord compression.

Case 1 presented with a history of intermittent tremors and right forelimb lameness. Clinical examination revealed an expansive, ill-defined, non-movable, soft tissue mass palpable on the right hemithorax and a mild pelvic limb paraparesis. Computed tomography (CT) revealed a large mass with evidence of infiltration into the thoracic vertebrae and spinal canal at the level of the thoracic (T) vertebrae 1-3. En bloc resection of the extra-spinal portion of the mass was performed followed by careful debridement of the affected spinal processes and removal of the spinal canal portion of the tumor. Histopathological evaluation confirmed an infiltrative lipoma with compressive osteolysis of the dorsal spinal processes. Within 24 hours after surgery, clinical signs disappeared. Follow up CT at 2 and 38 months, and examination at 10, 24, 32 and 38 months after surgery showed no evidence of remaining tumor mass or recurrence of clinical signs. The dog died of non-related disease at 51 months after surgery. Case 2 presented with a large, and slow growing mass over the right lumbar area, that had been present since birth. The dog did not show any clinical or neurological signs. MRI identified a mass extending from T13 to the 6th lumbar (L) vertebrae, and infiltration into the spinal canal with spinal cord compression at the level of Ll-L5. En bloc resection of the extraspinal portion of the mass was performed, followed by meticulous removal of the involved parts of the vertebrae and intraspinal portion of the mass. Histopathological evaluation confirmed infiltrative lipoma, with no obvious infiltration of the bone. Follow up MRI at 6, 18 and 30 months, showed remnant lipoma tissue in the retroperitoneal space without spinal involvement. At 45 months after surgery, the dog was still free of clinical signs.

It is concluded that en bloc resection with meticulous local debridement of infiltrative lipomas causing spinal cord compression can render long-term local disease control.