Management of Spinal Astrocytoma with Conservative Surgery and Radiotherapy

Twenty-seven patients with histologically verified spinal astrocytoma were treated at the Royal Marsden Hospital with postoperative radiotherapy. All patients had previous surgery; 10 had partial resection and 17 biopsy alone. All patients received involved field radiotherapy to a median dose of 50 Gy in 33 fractions. Overall 5- and 10-year survival was 59 and 52%, and progression free survival was 38 and 26% at 5 and 10 years, respectively, at a median follow-up of 6.5 years. Following radiotherapy, eight patients showed functional improvement, 15 were unchanged and two deteriorated. Sixteen patients relapsed, eleven at the primary site and five elsewhere in the CNS. Low grade histology, female gender and the presence of intramedullary cysts were favourable prognostic factors for survival on univariate analysis. The extent of surgery was not a significant predictor of survival. It is not possible to define the precise role of radiotherapy. However, all patients had residual tumour prior to irradiation, and 53% of low grade and 33% of high grade gliomas remained controlled locally at 3 years with stabilization or improvement in neurological function in all but two patients. This suggests that radiotherapy may result in temporary disease control analogous to cerebral gliomas.