Diagnosis And Treatment Of Glioblastoma

Causes

As of yet, no evident cause of glioblastomas has been found. There are several risk factors that may increase your chances of having a glioblastoma and these include your age, your sex (males are more susceptible), and exposure to radiation. Genetic disorders such as neurofibromatosis or Turcot syndrome have been shown to have an increased risk of glioblastomas.

Symptoms

Symptoms associated with glioblastomas are:

• Dizziness

• Headache

• Nausea

• Vomiting

• Seizures

• Memory deficits

• Changes in personality

Not all symptoms may occur in every case, and each case may have its own specific symptoms based on the location of the tumor.

Diagnosis

The tumor is diagnosed based on the following factors:

• MRI and CT scans, for locating the position of the tumor

• Biopsy where a small section of your tumor tissue is removed and thoroughly examined under a microscope. This gives information on the tumor's composition, so the best line of treatment can be devised.

In addition to these two main types of diagnosis, a detailed medical history is taken and a neurological and physiological exam that tests your memory, vision, balance and coordination, amongst other physical and cognitive abilities, is also carried out.

What are the treatments for glioblastoma?

Surgery

The first line of defense against a glioblastoma is surgery. The aim of the surgery is to remove as much of the tumor as possible and relieve the pressure that it exerts on the brain. The glioblastoma surgery is commonly performed under general anaesthesia. Here’s an overview of the procedure:

• The surgeon will first perform a craniotomy, which is the removal of a part of the bone from the skull to open access to the brain.

• The surgeon will then proceed to remove the tumor, or as much of it as possible, using specified surgical equipment and tools. Glioblastomas are infiltrative tumors, which makes them hard to completely remove.

• If the tumor is located in a vital brain area or is particularly difficult to locate, then intraoperative MRI or brain mapping will be used whilst performing the surgery.

• The surgeon will finish the operation by replacing the skull bone and suturing the cut on the scalp.

Radiation Therapy and Chemotherapy

Radiation and chemotherapy are employed following the surgery, or immediately in case the surgery is not possible. The main aims of these therapies are to kill any remaining cancerous cells that were not removed during surgery, to shrink the tumor.

Radiation therapy works by aiming high-energy rays at the tumor to kill cancerous cells. Chemotherapy, on the other hand, is a pharmacological treatment which is most often taken orally during and after radiation therapy. The most commonly prescribed chemotherapy drug for glioblastoma is temozolomide or Temodar.

Tumor treating field (TTF) therapy

TTF therapy is a relatively new form of treatment for glioblastomas. It works by blocking cell division using low-intensity electrical fields that have alternating frequencies. Adhesive pads are applied to the scalp, which are attached to a patient-controlled device that generates the necessary electrical fields.

What should I expect from this procedure?

A glioblastoma is a high-grade brain tumor that grows quickly, affecting neighbouring brain tissue. They can arise spontaneously at the grade IV level or develop from a lower grade astrocytoma.

Treating these tumors is difficult because they are heterogenous, that is, made up of different cells. Some of these cells react to the treatments and some do not, which subsequently grow further and spread across the brain. Hence, the success of the various treatments is short lived. Furthermore, as the disease occurs in the brain, there is the added disadvantage of working around the blood-brain barrier which severely restricts the kind of medications that can be prescribed.

As an end note, the prognosis is mostly critical but in many cases patients may be referred to a clinical trial, which could prove to be extremely helpful. Having family and friends around, keeping up with activities that you enjoy and taking care of your emotions are an integral part of the treatment.

Scientific advancements: Immunotherapy as a possible treatment for Glioblastoma?

Our immune system is our body’s own defense mechanism. It provides resistance against unknown or foreign bodies and damaged cells. Mutations occur constantly in our cells and this is another concern that our immune system usually takes care of. That being said, sometimes the occurrences of mutations ‘outruns’ our immune system and the cell becomes malignant and can develop into a tumor. As mentioned earlier, glioblastomas are one of the most aggressive brain tumors. A hallmark of the disease is to actively suppress the brain’s immune system. The brain has its own immune environment of which the blood-brain barrier is a vital component.

Immunotherapy is a developing field that aims to provide treatment for cancer by supporting or boosting your immune system, so it can better fight the disease. Whilst it has proven benefits for certain types of cancer such as lung or skin cancer, the research for its use against glioblastoma is still ongoing. The mechanisms that are involved in the regulation of the brain’s immune system are not fully understood, but current scientific advances are being made in developing individualised vaccines for patients. It is important to know that there are immense challenges that have to be overcome, and the future of its application to glioblastoma is still uncertain. Any progress will require time and the joint effort of scientists from different fields.