Astrocytomas are tumors of cells called astrocytes that have a role in the structure and function of the brain. These tumors are graded on the basis of their features under the microscope. While there are a number of grading systems, astrocytomas generally fall into one of three categories:
Low grade astrocytomas (least aggressive)
Anaplastic astrocytomas (more aggressive)
Glioblastoma
multiforme (most aggressive)
The initial treatment of low grade astrocytoma consists of maximal surgery. The role of radiation therapy has been disputed, but younger people with minimal residual disease after surgery may have radiation therapy deferred as long as there is adequate monitoring of the tumor by MRI or CT scanning.
Anaplastic astrocytoma has traditionally been treated similar to glioblastoma. Traditionally, radiation therapy has been followed by a combination of chemotherapeutic agents called PCV (procarbazine, CCNU, vincristine). Because of long-term toxicity attributable to CCNU, other forms of treatment are being investigated.
Astrocytoma, like glioblastoma and other brain tumors, require a number of conditions for growth. These include:
The ability of the tumor cells to divide (cell division).
The ability of the tumor cells to move through the brain (cell motility).
The ability of tumor cells to form a new blood supply to meet their need for nutrition and oxygen
(angiogenesis).
While radiation therapy affects all factors, traditional chemotherapy, for the most part, has targeted cellular division only. However, new classes of anti-tumor drugs targeting cell motility and angiogenesis (most notably thalidomide) are either in development or in clinical trials.
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Thalidomide |
Chemotherapy |
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Glioblastoma |
Tamoxifen and other less toxic therapies |
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Clinical Trials |
Radiation Therapy |