All about low-grade astrocytomas
It has been a while since I read up on my tumor. I thought I'd post some of the goods here.
What follows is from the American Brain Tumor Association.
Low-grade astrocytomas are relatively uncommon tumors when compared to their higher-grade counterparts; only about 1500 are believed to occur in North America each year. Their cause is unknown, and current research indicates that the environment does not seem to play a role in their origin.
Diffuse astrocytomas (what Liz has) typically arise in young adults, although they are also found in children and senior citizens. They may be found anywhere in the brain, but are most common in the cerebral hemispheres – the “thinking” part of the brain. (But not in Liz's case--her's is in the parietal lobe. Why am I talking about myself in third-person?) As the name implies, the borders of a diffuse astrocytoma tend to grow into surrounding normal brain tissue. Seizures and headaches are very often the earliest signs of this tumor; weakness on one side of the body (hemiparesis) is also common.
Once a scan shows an abnormality suspected of being a low-grade astrocytoma, the next step is generally a consultation with a neurosurgeon or neuro-oncologist. The neurosurgeon may recommend a biopsy to confirm the diagnosis or surgery to remove the tumor. When tumors are located near vital brain areas, neurosurgeons may use sophisticated techniques including functional MRI and intraoperative surface mapping of brain function to help with tumor removal. However, if this is a diffuse astrocytoma (which is what Liz has), the tumor usually has already grown tiny microscopic tentacles that spread into the surrounding brain tissue. Those tentacles cannot always be seen by the neurosurgeon and intermingle with brain cells that are performing their normal important functions; thus “complete” tumor removal may not be possible. The extent of surgery depends on the location of the tumor, the patient’s symptoms and personal preferences, and the neurosurgeon’s philosophy.
Once the diagnosis of diffuse low-grade astrocytoma is confirmed by tissue examination, the next issue is the type and timing of subsequent therapies. Options may include radiation, chemotherapy, or even careful observation. (I removed all the boring info about various treatment options.)
When diffuse astrocytomas recur following treatment, they frequently come back as a biologically more aggressive tumor. People with these tumors are generally eligible for the full spectrum of clinical trials available to patients with high-grade gliomas. Those clinical trials are testing novel treatment approaches ranging from stimulation of the body’s natural immune system to drugs which choke off the tumor’s blood supply (a technique called anti-angiogenesis inhibition) to drugs that selectively target biochemical pathways revved up in tumor cells, but inactive in healthy cells (signal transduction inhibition). Thus, progress in the more common high-grade gliomas should eventually translate into a better outcome for patients with diffuse astrocytomas.
