Primary Spinal Astrocytomas: A Literature Review

Abstract

Primary spinal astrocytoma is a subtype of glioma, the most common spinal cord tumor found in the intradural intramedullary compartment. Spinal astrocytomas account for 6-8% of all spinal cord tumors and are primarily low grade (World Health Organization grade I (WHO I) or WHO II). They are seen in both the adult and pediatric population with the most common presenting symptoms being back pain, sensory dysfunction, or motor dysfunction. Magnetic Resonance Imaging (MRI) with and without gadolinium is the imaging of choice, which usually reveals a hypointense T1 weighted and hyperintense T2 weighted lesion with a heterogeneous pattern of contrast enhancement. Further imaging which may aid in surgical planning includes computerized tomography, diffusion tensor imaging, and tractography. Median survival in spinal cord astrocytomas ranges widely. The factors most significantly associated with poor prognosis and shorter median survival are older age at initial diagnosis, higher grade lesion based on histology, and extent of resection. The mainstay of treatment for primary spinal cord astrocytomas is surgical resection, with the goal of preservation of neurologic function, guided by intraoperative neuromonitoring. Adjunctive radiation has been shown beneficial and may increase overall survival. The role of adjunctive chemotherapy is employed, however, its benefit has not been clearly defined. Primary spinal cord astrocytomas are rare and challenging to treat. The gold standard treatment is surgical resection. Second-line treatments include radiation and chemotherapy, although, the optimal regimen for adjunctive therapy has not yet been clearly defined.

Keywords: astrocytoma; glioblastoma; glioma; intradural; intramedullary; spinal astrocytoma; spinal cord neoplasms; spinal tumor.

Figure 1. Pilocytic astrocytoma of the thoracic spine.

A) T1-weighted sagittal pre-contrast image, B) T1-weighted sagittal post-contrast image, and C) T2-weighted axial slice showing displacement of thoracic cord by area of hyperintensity consistent with spinal astrocytoma. Photo Reference: Courtesy of Assoc. Prof. Frank Gaillard, Radiopaedia.org, rID: 19536

Figure 2. High-grade astrocytoma of the thoracic spine.

A) T1-weighted sagittal pre-contrast image, B) T1-weighted sagittal post-contrast image, and C) T2-weighted axial slice showing displacement of the thoracic cord by area of hyperintensity consistent with spinal astrocytoma. Photo Reference: Courtesy of Assoc. Prof. Frank Gaillard, Radiopaedia.org, rID: 19536