ABSTRACT
Astrocytomas Introduction Astrocytoma (from the Greek word ‘astro’ for star) refers to the stellate shape of some astrocytes. Diffuse astrocytic tumors can be divided by histologic characteristics into astrocytoma, a low-grade tumor, and anaplastic astrocytoma and glioblastoma multiforme, both high-grade tumors (Fig. 5.2). Also included in this group are tumors that diffusely infiltrate all or much of the brain without necessarily forming a mass lesion (gliomatosis cerebri) and tumors restricted to the brainstem (brainstem gliomas); both may be of either grade. Because of different age and growth characteristics, and because their location often precludes biopsy, brainstem gliomas are considered separately from supratentorial gliomas. Almost by definition, diffuse astrocytomas, even those that appear to be histologically discrete, are not amenable to surgical cure.
