Conservative surgery and radiotherapy in the treatment of spinal cord astrocytoma.

Spinal cord astrocytomas are rare neoplasms, and optimal treatment guidelines are undefined, 23 patients with spinal cord astrocytomas were treated between 1984 and 1993 with conservative surgery and postoperative radiotherapy. The mean age was 31 years. Twelve patients were male and eleven female. All patients presented with neurologic deficit. Cervical cord was involved in five patients, cervicothoracic in four, thoracic in eight and thoracolumbar in six. Five patients had intramedullary cysts. Fifteen patients had low grade tumors and six high grade. Surgery was near total excision in three patients, partial excision in ten and biopsy in ten patients. All patients received postoperative radiotherapy to a median dose of 45 Gy in 25 fractions over 5 weeks. The median followup was 51 months (range 7-143 months). At 6 months post radiotherapy, twelve patients had improvement of neurologic status, nine had stable status, and two deteriorated. The actuarial overall survival was 55% at 5 years and 39% at 10 years. The actuarial progression free survival probability was 75% at 5 years and 55% at 10 years. Five patients had local failure and two failed at distant sites. Twelve patients died, six due to progressive disease, five due to complications of paraplegia and one patient of unrelated causes. Tumor grade was a significant prognostic factor for overall survival. 5 year overall survival was 79% for low grade tumors. No patient with high grade tumor survived more than 2 years and the median survival was 10 months. Low grade, female sex and presence of intramedullary cysts were associated with significantly improved progression free survival. Conservative surgery followed by radiotherapy appears to have a role in achieving tumor control and neurologic recovery in patients with low grade astrocytomas of the spinal cord. Treatment results of high grade tumors remain poor and new therapeutic strategies need to be studied.