[Clinical effects of microsurgery in spinal cord anaplastic astrocytoma]

Objective: To investigate the surgical outcomes and prognosis of spinal cord anaplastic astrocytoma (AA). Methods: A total of 27 consecutive patients diagnosed as spinal cord AA between January 2008 and May 2015 in Department of Neurosurgery of Beijing Tiantan Hospital were retrospectively reviewed. There were 18 males and 9 females, the mean age was (30.7±13.0) years (ranging from 5 to 52 years). The lesions were located at cervical level in 8 patients, at thoracic level in 9 patients, at cervicothoracic level in 3 patients, and at thoracolumbar level in 7 patients, the average number of vertebral was 3.3±1.3.The median time from onset of symptom to surgery was 4 months, ranging from 3 days to 48 months. The clinical presentations were weakness (23 cases), paresthesia (22 cases), pain (20 cases), sphincter disorder (15 cases) and paralysis (7 cases). The preoperative modified McCormick scale was as follows: grade Ⅱ for 6 cases, grade Ⅲ for 7 cases, grade Ⅳ for 7 cases, grade Ⅴ for 7 cases. The tumors were surgically removed via posterior median approach with the monitoring of the somatosensory-evoked potentials to minimize the neurological injury. All of the patients were recommonded to receive adjuvant chemotherapy and radiotherapy postoperatively after pothological verified and followed up by clinic interview or telephone postoperatively. Log-rank test was used to calculate the survival rate. Results: Gross total resection and subtotal resection were achieved in 18 patients and partial resection in 9. Twenty patients received adjuvant chemotherapy and (or) radiotherapy, 7 patients did not received chemoradiation postoperatively. Nineteen patients died and 8 were alive at the last follow-up. The median survival time was 23 months with 1 and 2-year survival rates of 85.2% and 50.0%.There was no statistical significance between subtotal resection group and partial resection group(χ(2)=0.089, P=0.880), the survival rates of patients in chemotherapy group and radiotherapy group were increased significantly(χ(2)=6.687, P=0.001; χ(2)=14.887, P=0.002). Conclusions: Spinal cord AA is a rare spinal high-grade astrocytoma with aggressive nature, the prognosis remains poor even after comprehensive treatments. Microsurgery followed by adjuvant chemoradiation is recommended for the treatment.