Primary Lumbar Extradural Hemangiosarcoma in a Dog

A 9 yr old castrated male golden retriever weighing 36 kg was presented for evaluation of progressive left pelvic limb paresis and fecal and urinary incontinence. MRI demonstrated an extradural, ovoid mass compressing the lumbar spinal cord. Surgical excision of the mass was performed. Histologically, the mass was consistent with hemangiosarcoma with no involvement of the adjacent vertebrae. The dog underwent a doxorubicin-based chemotherapy protocol with the addition of oral cyclophosphamide. After completion of chemotherapy, the dog was evaluated q 4 mo for restaging. Clinicopathological evidence of primary tumor recurrence or metastatic disease was not detected for 15 mo after initial diagnosis and treatment. To the authors' knowledge, this is the first report of a primary extradural hemangiosarcoma in the lumbar vertebral column in a dog. The clinical presentation, diagnosis, treatment, and outcome are also discussed.