Introduction to the Human Brain and Brain Tumours

This article will summarise what the brain looks like, the purpose of its use, and what the Quran says about this particular organ, the different types of brain tumours, how is it tested, types of treatments available.

THE BRAIN IS DIVIDED INTO SECTIONS AND SUB-SECTIONS...

The brain consists of three main parts the cerebrum, cerebellum and brain stem. The cerebrum consists of different regions known as lobes that have specialised functions. The cerebellum is responsible for posture, balance and the vital centres (cardiac/respiratory/vasomotor centres). The brain stem role is to focus on the vital centres as well as the motor and sensory pathways.

What is the Quran and what does the Quran say about the brain?

The Quran is the holy book in which Muslims believe in and are sacred words of Allah (God). It was revealed in stages to the Prophet Muhammad peace be upon him in Arabic.
Previously, for many centuries, it was theoretically believed that the role of the frontal part of the brain (forehead) known as the prefrontal vortex of the cerebrum is vision because it was located near the eyes. 

Today, amongst the physiology books you will discover that the function of this particular area of the cerebrum is to plan and initiate movements that occur in the anterior portion of the frontal lobes and this is a region of association cortex. It is also a location for motivation where it is thought to be functional centre for ‘aggression’. In the Quran, Allah states in 96:16 

‘A lying sinful forehead’.

The Quran notes that those who disbelieved will be dragged from the forehead. Thus how can today’s explanation of this particular area of the cerebrum linked to ‘lying, sinful forehead’? The prefrontal cortex is responsible for planning and initiating good and bad actions as well as for telling the truth and lies. 

This was revealed 1400 years ago? Isn’t this miraculous? Professor Keith Moore notes that scientists have only discovered these facts 6 decades ago.

Malignant, Benign, cancer, neoplasm, tumour...what do they all mean?

A tumour is a neoplasm that refers to a mass. A neoplasm is an abnormal growth of cells that grow quicker than normal cells and will continuously grow unless treated. Benign means non-cancerous and is generally harmless. Benign tumours can be easily treated however if left untreated it can grow large and lead to other diseases due to its size. Another reason why benign tumours need to be treated is it can mimic malignant tumours. Malignant tumours are cancerous and are often resistant to treatment and can spread to other areas of the body and they can sometimes come back after have been removed.

What is a brain tumour?
Brain tumours can be divided into primary or secondary. A primary brain tumour initiates in the brain and have not spread there from a different organ. Secondary brain tumours are those that have spread to the brain from a different organ of the body.

What are the causes of brain tumour?
The cause for majority of brain tumours is unknown. Tumours are not infectious so they cannot be passed onto others.

Age – risk of developing brain cancer increases with age despite it can develop at any age. 

Gender – common in men than women

Radiotherapy – People who have had radiation exposure to the head, it can increase risk of brain tumour.

Genetic conditions – For instance, neurofibromatosis type 1 and type 2, tuberous sclerosis, or the following syndromes: Von Hippel-Lindau, Li-Fraumeni, Gorlin.Turcot

Other possible risk factors such as viruses, mobile phones have been suggested.

What are the types of cancers?
Glial cells 
Glial cells are supporting cells of the brain. Majority of brain tumours develop from glial cells and are known as gliomas. There are different types of glial cells, thus different forms of gliomas are formed: 

1) Oligodendroglial tumours – These are made from glial cells called oligodendrocytes whose role normally is to cover nerve cells (myelin sheath). 
2) Astrocytic tumours – Most common type of glioma and develop from star-shaped cells called astrocytes.
3) Mixed glioma - This is where a range of different types of glial cells are involved. For instance, oligo-astrocytomes – a mixture of oligodendrocytes and astrocytes.

Ependymal tumours 
These are rare type that develops from ependymal cells. They line the ventricles (fluid spaces in brain) and central canal (area on spinal cord).

Meningioma 
These arise from the meninges. Meninges are membranes that cover the brain. Tumours can occur in any area of the meninges and grow very slowly.

Pineal region tumours. 
There are two cerebral hemispheres: right and left. The pineal gland is located where the two hemispheres are linked together. It is a rare tumour and is made up of different types of cells that determine the rate of the growth where some are slow-growing and others are fast-growing.

Spinal tumours 
This is normally caused by pressing on spinal nerves. In some cases, a tumour in the lower area of the spinal cord can cause loss of control of bladder or bowel. 

Medulloblastomas 
It is a type of primitive neuroectodermal tumour (PNET). PNET are cells remaining from early stages of development of the baby in the womb. This is amongst the common malignant brain tumours in children but is rare in adults. They develop in the cerebellum then spread to other areas of the brain. There are rare cases where medulloblastomas spread out of the brain to lymph nodes or the lungs.

Haemangioblastoma.
This is a rare type of slow-growing, benign tumour and develops from cells that line blood vessels. 

Central Nervous System (CNS) lymphoma.
It is a malignant tumour that develops in the lymphatic system. Lymphatic system is part of the immune system that aims to protect the body from infection and diseases. The system consists of lymph nodes, spleen, thymus and bone marrow. In rare cases, they only affect the brain and is known as primary CNS tumours.

Pituitary tumours.
They are benign and are called pituitary adenomas.

Acoustic neuroma
They are benign tumours that develop in the acoustic/auditory nerve. This nerve controls balance and hearing and is covered by Schwann cells. This is where the tumour initiates and is known as schwannoma. They are normally found in adults especially in people with neurofibromatosis type 2 (NF2); a genetic condition.

How to treat brain tumours?
There are a range of treatments available such as chemotherapy, radiotherapy, surgery that can be used alone or a combination of these treatments. The type of treatment given to the patient is dependent on a number of factors: grade, type, size, position of the tumour as we as the overall general health. Surgery can range from a simple operation such as having a biopsy to a more complicated to having it completely removed. 

Normally for majority of primary tumours, surgery is the first treatment where the tumours can be removed without causing damage towards the rest of the brain tissue. However, there are some types of brain tumours where surgery should be last treatment used, not used immediately or not at all. For instance, some gliomas that are low-grade can be treated with radiotherapy without chemotherapy or can be closely monitored. Lymphomas can be treated with a combination of chemotherapy and radiotherapy rather than surgery. 

After surgery, radiotherapy is often used if the tumour has not been completely removed or abnormal cells are left behind. However for high grade tumours, radiotherapy is still recommended even if the tumour that is obvious has been fully surgically removed. 

The next topic I will talk about is viruses? what are viruses? what is the relationship between viruses and cancer?. This will be released on Wednesday God Willing.