Glioblastoma multiforme

Brittany Maynard’s  decision to opt for “assisted suicide for the terminally ill” highlights a very poorly understood type of primary brain cancer called glioblastoma multiforme. Tumors that start in the brain rather than from somewhere else in the body are called primary brain tumors. Such tumors are fairly rare and glioblastoma multiforme is an even rarer form of the disease.

So to understand Brittany’s decision, I think it’s important to understand the disease and the medical treatment involved.

The brain is not just made of neurons, though it’s the commonly heard term.  We often tend to think of them as being the only cell that makes up the brain and the nervous system in general. The neuron is certainly the star of the show as it generates the electrical signals that helps the brain function. The neurons are high maintenance as they require tons of energy, salts and vitamins to do its job. The neuron cannot reproduce and it cannot heal itself either and is a very delicate cell.

The glial cells are the ‘support’ cells of the brain. They handle all the background operations so that the neuron can go about doing it’s highly specialised job uninterrupted. They have many different names, shapes and functions.
For example, the oligodendrocyte forms a protective layer of insulation around parts of the neuron, helping them propagate signals efficiently and speedily. They also help the cell heal.

The cells called ependymal make the highly nutritive cerebro spinal fluid(CSF). The CSF bathes the neuron and provides nutrition without exposing the sensitive neuron to blood directly. Ependymal cells are stem cells for the brain as well as the spinal cord.

The most common helper or glial cell in the brain is the “astrocyte”. These cells are important for healthy functioning of the brain. They protect neurons, regulate blood flow and concentration of ions around the cells. They help neurons heal when injured and they also communicate with each other using calcium ion exchange to form a second flow of information in the brain.

These cells reproduce very fast and have a devastating effect in case of genetic damage or if the cells become cancerous. They can outgrow any attempt of the immune system to kill the mutant cells. Such cancerous astrocytes cause glioblastoma multiforme.

Astrocytes are the main cells that control the blood flow in the brain, so when they become cancerous, they cause an increase in the concentration of blood to nourish the growing tumor. This is one of the chief reasons why gliolastomas are aggressive and tough to kill.

Another problem with regard to managing gliobastomas is the problem of clinical presentation. Brain tumors in general present with vague symptoms that delay recognition. Since gliolastomas are aggressive, by the time a person realizes that something is wrong and they need help, the tumor would have already caused a massive amount of destruction. Glioblastomas grow quickly as the astrocytes divide rapidly.

The increased pressure in the brain causes initial symptoms like:

• Headache
• Nausea
• Vomiting
• Drowsiness

Depending on where the tumor is, the patient can develop many other symptoms. Extreme examples being weakness on one side of the body, memory and/or speech problems and visual problems.

The treatment for glioblastoma is difficult and a 5 year survival rate for this kind of tumor is a testament to medical research and well trained neuro-oncology teams. The tumor responds to a combination of therapies that include surgery, chemotherapy and radiation.

The first step in managing a glioblastoma is to relieve the pressure symptoms. This usually means surgically removing as much of the tumor as is safely possible. Most glioblastomas have finger-like tentacles that invade the healthy tissue of the brain, which makes it almost impossible to remove the entire tumor in one surgery, or any at all for that matter. The closer the tumor mass or the tentacles get to vital areas of the brain, the less likely it is for the neurosurgeon to remove it. Radiation and chemotherapy are then used to slow the growth of tumors that cannot be removed surgically.

Brittany’s struggle is an intensely personal one and I salute her willingness to share it with us. She has provided the rest of the world, the chance to raise awareness about the plight of patients with these kinds of aggressive cancers. No matter where you fall on the ideological spectrum, when it comes to the ethics of her decision in general, I encourage the readers to educate themselves about the disease itself and spread awareness of the issue.