Prognostic factors and survival in patients with spinal cord gliomas after radiation therapy

The purpose of this study was to determine the impact of various prognostic factors on survival in spinal cord gliomas treated with radiation. Fifty-three patients with spinal cord gliomas irradiated at three major institutions were studied. Fifty-one patients were classified as having ependymoma, astrocytoma, or both. Two patients were classified as having gliomas (otherwise unspecified). Eleven patients had complete resection of their tumor. Biopsy or partial resection was done in the remaining patients. All patients received external beam radiation. Information on these patients was placed in a central database file and analyzed for the effect of several prognostic factors on survival. Overall survival of the entire group was 76.9% and 61.5% at 5 and 10 years, respectively. Pathologic status significantly affected survival (p = 0.03). Patients with ependymomas had a 5-year survival of 93.8% and a 10-year survival of 67.5%. Patients with astrocytoma had a 5-year survival of 64.2% and a 10-year survival of 54%. Univariate analysis showed pathology and the presence of cysts (p = 0.038) to significantly affect survival. Age, sex, location of the primary, extent of surgery radiation dose, and number of involved segments did not affect survival. On multivariate analysis, astrocytic pathology, involvement of more than five segments, male sex, and the absence of cysts (in or adjacent to the tumor) were associated with a significantly inferior survival. This study confirms the importance of pathology and number of segments involved in determining outcome or survival. The presence of cysts adjacent to or within the tumor was found to be associated with an improvement in survival.