Spinal Cord Astrocytoma

Introduction

Spinal cord astrocytomas are quite uncommon and account for only 3% to 4% of all central nervous system (CNS) astrocytomas. Furthermore, although intracranial glioblastomas are the most common primary brain parenchymal neoplasm, spinal cord glioblastomas are exceedingly rare.

The characteristic asymmetric location of small spinal cord astrocytomas is due to the location of their peripherally located astrocytic cells of origin, as well as their affinity to grow along the spinal cord white matter tracts. Both on gross inspection and imaging evaluation, astrocytomas tend to be poorly defined with infiltration beyond the visible margins ( Figs. 34.1 and 34.2 ).

At the time of diagnosis many of these lesions are often quite extensive, on average covering five vertebral segments. These infiltrating astrocytomas therefore appear as expansile, T1 isointense/hypointense and T2 hyperintense lesions often spanning multiple levels ( Fig. 34.3 ). An association with NF-1 exists.