Glioma
This group comprises anaplastic astrocytomas and glioblastoma multiforme. Whereas the median overall survival of anaplastic (WHO grade III) gliomas is approximately 3 years, glioblastoma multiforme has a poor median overall survival of c. 15 months.
Astrocytoma
For low-grade astrocytomas, removal of the tumor generally allows functional survival for many years. In some reports, the 5-year survival has been over 90% with well-resected tumors. Indeed, broad intervention of low-grade conditions is a contested matter. In particular, pilocytic astrocytomas are commonly indolent bodies that may permit normal neurologic function. However, left unattended, these tumors may eventually undergo neoplastic transformation. To date, complete resection of high-grade astrocytomas is impossible because of the diffuse infiltration of tumor cells into normal parenchyma. Thus, high-grade astrocytomas inevitably recur after initial surgery or therapy, and are usually treated similarly as the initial tumor. Despite decades of therapeutic research, curative intervention is still nonexistent for high-grade astrocytomas; patient care ultimately focuses on palliative management.