Treatment of experimental spinal cord compression caused by extradural neoplasms

Epidural spinal cord compression was produced in rats by injection of Walker 256 carcinoma cell suspension anterior to the T-12 or T-13 vertebral body. The tumor grows through the intervertebral foramina to compress the spinal cord and produce paraplegia in 3 to 4 weeks. The effect of several treatments upon clinical signs was assessed. Dexamethasone caused a significant but transient improvement in neurological function. Radiation therapy likewise improved neurological function, and was more effective when given by a high-dose protracted course than when given either in a single dose or a low-dose protracted course. Laminectomy was not helpful in relieving neurological symptoms. Dimethyl sulfoxide did not relieve neurological symptoms. Cyclophosphamide was most effective in relieving neurological symptoms, and most of the animals that were treated with that drug when they were severely weak but still able to move their hind limbs recovered fully. Some animals that were totally paraplegic when treatment began recovered function after radiation therapy or cyclophosphamide treatment, but recovery was better if treatment was started when animals could still move their hind limbs. This animal model appears to be a useful way of studying the treatment of human spinal cord compression produced by epidural neoplasms.