Long-Term Outcomes of Patients With Spinal Cord Gliomas Treated by Modern Conformal Radiation Techniques

Abstract

This study retrospectively examines the long-term therapeutic outcomes of 32 patients with primary spinal cord gliomas at Massachusetts General Hospital between 1991 and 2005 treated by either photon intensity-modulated radiotherapy or conformal proton radiotherapy. Individual patient tumor types included 14 ependymomas, 17 astrocytomas, and one oligodendroglioma. Twenty-two patients were treated with photon beam radiation therapy, and 10 patients were treated with proton beam therapy. The overall survival and time to progression were analyzed. Average radiation dose for patients was 51 Gy in 1.8 median daily fractions over 29 treatments. For all 32 patients, the overall 5-year survival was 65% and the progression-free survival was 61%, respectively. Overall survival was significantly worse for patients more than 55 years of age (p=0.02). Ependymoma patients had significantly longer survival times than astrocytoma patients (p=0.05). Patients who had undergone a biopsy developed worse outcomes then those with a resection (p=0.05). With the caveat of a limited number of patients, the multivariate model seems to suggest improved overall survival for younger patients (<54 years of age), ependymoma histology, and photon vs. proton treatment. For patients with spinal cord gliomas, significant factors associated with patient outcome include tumor pathology, age, extent of surgery, and treatment.