Glioblastomas, also known as glioblastoma multiforme (GBMs), are a relatively common type of glioma, which develop from the glial (or supportive) cellsthe basic structural and functional unit of all living things in the central nervous system (CNS). More specifically, they develop from a type of glial cell called astrocytes, a star-shaped cell that has a variety of functions, including regulating bloodthe red bodily fluid that transports oxygen and other nutrients around the body flow and regulating and maintaining synapses. Glioblastomas are classified as a high-grade astrocytoma.
The brain is a complex organ that is responsible for controlling all functions of the body. It has five main portions: the cerebrum, cerebellum, brainstem, pituitary gland, and hypothalamus. The cerebrum is the biggest part of the brain, and consists of the frontal, parietal, temporal, and occipital lobes. This part of the brain is responsible for voluntary movement, intelligence, and memory, and is often where glioblastomas develop. The cerebellum is a small part of the brain located at the back of the head, and regulates posture and balance. The brainstem is a small, stalk-like structure towards the bottom of the brain that connects the brain to the spinal cord. It regulates many vital bodily processes, such as swallowing, breathing, and heart rate. The pituitary gland is a pea sized organ located behind the eyes, and is responsible for the production and secretion of hormones in the body. The hypothalamus is located deep within the brain, and has many important functions, such as producing and secreting different hormones, regulating temperature, and controlling appetite.
The spinal cord is a long, thin, tubular structure that extends down from the brainstem to the lower back. It is made of nerve tissuea group of cells that work together to perform a function, and is surrounded by the bones of the spine (vertebrae). The spinal cord is responsible for transmitting nerve signals from the brain to the body, and vice versa. It has motor functions (such as voluntary movement), sensory functions (such as pressure, touch, temperature, and pain), and autonomous functions (such as regulating digestion, heart rate, and blood pressure).
Glioblastomas are more common in males, and tend to develop between the ages of 50-80. However, anyone can develop this disease.
Variants of Glioblastoma
There are three primary variants of glioblastoma, which are classified by their cellular appearance under the microscope.
Giant Cell Glioblastoma
Giant cell glioblastomas are a rare form of glioblastomas that are categorised by large malignantcancerous, may grow and spread to other areas of the body cells under the microscope. It was previously referred to as a monstrocellular tumoura tissue mass that forms from groups of unhealthy cells due to the large cells. These tumours are often non-aggressive, and often has a better prognosisto predict how a disease/condition may progress and what the outcome might be than other types of glioblastomas
Gliosarcoma
Gliosarcomas are a rare form of glioblastoma that contains elements of glial cells and sarcomas, which are traditionally cancers arising from bone and soft tissuetissue/the material that joins, holds up or surrounds inside body parts such as fat, muscle, ligaments and lining around joints. They are generally found along the surface of the brain, but can also develop along the spinal cord. Gliosarcomas are often aggressive, and may not have as good of a prognosis as other types of glioblastomas.
Epithelioid Glioblastoma
Epithelioid glioblastomas are a rare form of glioblastoma that contain epithelial cells, which are cells that line organs. They are generally found in the cerebrum, however they can develop in other locations. Epithelioid glioblastomas are often very aggressive, and may not have as good of a prognosis as other types of glioblastomas.
Treatment
When cancers are detected, they are staged and graded based on size, metastasiswhen the cancer has spread to other parts of the body, also known as mets, and how the cancera disease where abnormal cells split without control and spread to other nearby body tissue and/or organs cells look under the microscope. Stagingthe process of determining how big the cancer is, where it started and if it has spread to other areas and grading helps your doctors determine the best treatment for you. However, brain cancers are rarely staged, as they rarely spread to other parts of the body. Instead, they are generally graded from I-IV.
Glioblastomas and their variants are considered to be gradea description of how abnormal cancer cells and tissue look under a microscope when compared to healthy cells IV tumours, as the tumour cells appear very abnormal under the microscope and grow rapidly.
Once your tumour has been graded, your doctor may recommend genetic testinga procedure that analyses DNA to identify changes in genes, chromosomes and proteins, which can be used to analyse tumour DNA to help determine which treatment has the greatest chance of success, which analyses your tumour DNA and can help determine which treatment has the greatest chance of success. They will then discuss the most appropriate treatment option for you.
Treatment is dependent on several factors, including location, age, stage of disease and overall health.
Treatment options for glioblastomas may include:
- Surgerytreatment involving removal of cancerous tissue and/or tumours and a margin of healthy tissue around it to reduce recurrence to remove as much of the tumour as possible.
- Radiation therapya treatment that uses controlled doses of radiation to damage or kill cancer cells.
- Chemotherapya cancer treatment that uses drugs to kill or slow the growth of cancer cells, while minimising damage to healthy cells.
- Tumour treating fields (TTF) therapya procedure that uses alternating electric fields to disrupt cancer cell division.
- Targeted therapymedication that targets specific molecular features of cancer cells.
- Immunotherapya treatment that uses a person's immune system to fight cancer.
- Clinical trialsresearch studies performed to test new treatments, tests or procedures and evaluate their effectiveness on various diseases.
- Palliative carea variety of practices and exercises used to provide pain relief and improve quality of life without curing the disease.
Risk factors
Although it is a relatively common type of tumour, it is not clear what the riskthe possibility that something bad will happen factors of glioblastomas are.
Symptoms
Glioblastomas may appear asymptomatic in the early stages of disease. As the tumour progresses, some of the following symptoms may appear:
- Headaches (commonly in the morning, and may go away after vomiting).
- Nauseato feel sick or likely to vomit and/or vomiting.
- Difficulties with vision, hearing, and/or speaking.
- Loss of balance.
- Difficulties walking.
- Syncopefainting or passing out.
- Worsening handwriting and speaking skills.
- Weakness or changes in one side of the body.
- Fatiguea state of extreme tiredness or exhaustion, can be physical or mental.
- Changes in energy levels.
- Changes in personality and behaviour.
- Seizures.
- Unexplained weight loss/loss of appetite.
Not everyone with the symptoms above will have cancer, but see your general practitioner (GP) if you are concerned.
Diagnosis
If your doctor suspects you have a glioblastoma, they may order the following tests to confirm the diagnosisthe process of identifying a disease based on signs and symptoms, patient history and medical test results and refer you to a specialist for treatment:
- Physical examinationan examination of your current symptoms, affected area(s) and overall medical history.
- Neurological examinationan assessment of sensory and motor functions, such as vision, balance and coordination.
- Imagingtests that create detailed images of areas inside the body tests, potentially including:
- MRI (magnetic resonance imaging)a type of medical imaging that uses radiowaves, a strong magnet and computer technology to create detailed images of the body.
- CT (computed tomography) scana type of medical imaging that uses x-rays and computer technology to create detailed images of the body.
- PET (positron emission tomography) scana type of medical imaging that uses radioactive tracers to create detailed images of the body.
- Blood teststesting done to measure the levels of certain substances in the blood.
- Biopsyremoval of a section of tissue to analyse for cancer cells.
