What is Brain?
It is a soft, spongy tissue mass which is protected by:
• The skull bones
• 3 fine layer of tissue (meninges)
• Cerebrospinal fluid (Watery fluid) flowing through spaces between the meninges and through spaces (ventricles) within the brain.

The things that we choose to do like walking, talking, etc. and the involuntary things that we do like breathing are directed by the brain. The brain also controls ours senses (sight, sound, touch, taste and smell), memory, feelings and personality.
Messages are transmitted back and forth between the brain and the remaining body by a network of nerves. Few nerves travel directly from the brain to the eyes, ears and other parts of the head. Other nerves travel through the spinal cord for connecting the brain with the remaining body parts.
Inside the brain and spinal cord, nerve cells are surrounded by glial cells which hold them in place.

The 3 main parts of the brain regulate different activities:
• Cerebrum: By using the information from our senses the cerebrum tells us what is happening around us and instructs our body how to respond. Reading, thinking, learning, speech and emotions are
  controlled by it. The cerebrum is divided in two parts (hemispheres) namely right and left cerebral hemispheres. The muscles on the left side of the body are controlled by the right hemisphere. The
  muscles on the right side of the body are controlled by the left hemisphere.
• Cerebellum: The balance for walking and standing and other actions that are complex are controlled by the brain.
• Brain stem: The brain and the spinal cord are connected to each other by the brain stem. Breathing, temperature of the body, blood pressure and other basic functions of the body are controlled by it.

What is tumour?
Most normal cells perish, when they grow old or get damaged, and their place is taken by new cells. Sometimes, a flaw occurs in this process. Formation of new cells occur when the body doesn’t require them. Also, damaged or old cells don’t perish as they should. This extra build-up of cells usually forms a mass of tissue known as a growth or tumour.
The origin of Primary brain tumours is in the brain itself or in the tissues nearby it, such as in the membranes covering the brain (meninges), cranial nerves, pituitary gland or pineal gland.
Primary tumours commence when normal cells receive errors (mutations) in their DNA allowing the cells to grow and divide at increased rates and continue to live when healthy cells would perish. As a result, a mass of abnormal cells is formed called as tumour.
In secondary tumour, cancer begins at some other place and spreads to the brain. Secondary brain tumours are more frequent than primary tumours.

Various types of primary brain tumours exist getting their names from the type of cells involved. Examples include:
• Gliomas: These tumours commence in the brain or spinal cord. It includes astrocytomas, ependymoma, glioblastomas, oligoastrocytomas and oligodendrogliomas.
• Meningiomas: A tumour arising from the membranes surrounding your brain and spinal cord (meninges) is called Meningioma.
• Acoustic neuromas (schwannomas): Benign tumours developing on the nerves that regulate balance and hearing starting from your inner ear to your brain.
• Pituitary adenomas: Mostly these are benign tumours which develop in the pituitary gland at the brain’s base. These tumours may affect the pituitary hormones with effects observed throughout the
  body.
• Medullolastmas: Medulloblastomas are the most frequent cancerous brain tumours observed in children. It begins in the lower back portion of the brain and is likely to spread through the spinal fluid.
  Although these tumours occur in adults, they are less common.
• PNETs: Primary neuroectodermal tumours (PNETs) are rare cancerous tumours starting in the brain’s embryonic (foetal) cells. They can take place anywhere in the brain.
• Germ cell tumours: Germ cell tumours can begin during childhood where there will be formation of testicles or ovaries. But occasionally germ cell tumours progress to other body parts such as brain.
• Craniopharyngiomas: It is a rare, non-cancerous tumour beginning near the pituitary gland (gland secreting hormones that controls many functions of the body) of the brain. The pituitary gland and other
  structures near the brain are affected as the Craniopharyngiomas gradually grows.

Cancer that originates at other parts and spreads to the brain
Tumours that occurs from cancer that begins at other place in your body and later spreads (metastasizes) to your brain are called Secondary (metastatic) brain tumours.
Most often, secondary brain tumours occur in people having a history of cancer. But in rare cases, a metastatic brain tumour can be the initial sign of cancer that began somewhere else in your body. Secondary brain tumours are more frequent than primary tumours.

Any type of cancer can metastasize to the brain, but the most frequent types include:
• Breast cancer
• Colon cancer
• Kidney cancer
• Lung cancer
• Melanoma

Types and grades of tumour:

Primary brain tumour is either benign or malignant
a) Benign brain tumours don’t contain cancer cells:
    • Benign tumours can generally be removed, and they rarely grow back.
    • Normally benign tumours contain an obvious border or edge. Seldom do cells from benign tumours invade tissues around them. They do not metastasize to remaining parts of the body. Nevertheless,
      benign tumours can press on the brain’s sensitive areas causing serious health problems.
    • As opposed to benign tumours in majority of the body parts, benign brain tumours can be fatal.
    • There are chances of benign brain tumours becoming malignant.

b) Malignant brain tumour (also called brain cancer) have cancer cells:
    • Malignant brain tumours are commonly more serious and are usually life threatening.
    • They tend to grow quickly and crowd or invade the adjoining healthy brain tissue.
    • Breaking away from the malignant brain tumours, the cancer cells may spread to remaining parts of the brain or to the spinal cord.

Tumour Grade
Grades are used by doctors to group brain tumour. The way the cells appear under a microscope is used for grading a tumour.

• Grade I: The tissue is benign. The cells appear almost like normal brain cells, & they grow gradually.
• Grade II: The tissue is malignant. Compared to cells in a Grade I tumour, the cells appear less like normal cells.
• Grade III: The malignant tissue has cells that appear a lot different from normal cells. The abnormal cells are actively flourishing (anaplastic).
• Grade IV: The malignant tissue contains cells that appear most abnormal and likely to grow quickly.

Cells from lower-grade tumours (grade I and II) appear more normal and usually grow more gradually than cells from higher-grade tumours (grades III and IV).

Over a period of time, a lower-grade tumour can turn into a higher-grade tumour. Nevertheless, the change to higher-grade tumour occurs more frequently in adults than in children.

Types of Primary Brain Tumours
There are several categories of primary brain tumours. Primary brain tumours are given names according to the cells type or the part of the brain in which they start. For example, a majority of primary brain tumours originate in glial cells. This tumour type is known as glioma.

The most frequent types among adults are:
a) Astrocytoma: The tumour emerges from astrocytes (star-shaped glial cells). It may be any grade. In adults, an astrocytoma most frequently emerges in the cerebrum.
    • Grade I or II astrocytoma: It can be referred to as a low-grade glioma.
    • Grade III astrocytoma: It is at times referred to as a high-grade or an anaplastic astrocytoma.
    • Grade IV astrocytoma: It may be referred to as glioblastoma or malignant astrocytic glioma.

b) Meningioma: The tumour emerges in the meninges. It can be graded as I, II or III. It is generally benign (grade I) and grows slowly.

c) Oligodendroglioma: The tumour arises from cells that produce the fatty material that covers and protects nerves. It generally takes place in the cerebrum. It is observed most commonly in middle-aged
    adults. It may be grade II or III.

The most common types among children are:
a) Medulloblastoma: The tumour generally emerges in the cerebellum. It is sometimes referred to as primitive neuroectodermal tumour. It is grade IV.
b) Grade I or II astrocytoma: This low-grade tumour takes place anywhere in the brain in children. Juvenile pilocytic astrocytoma is the most frequently observed astrocytoma among children. It is grade I.
c) Ependymoma: The tumour originates from the cells lining the spinal cord’s ventricle or central canal. It most frequently observed in children and young adults. It can be grade I, II or III.
d) Brain stem glioma: The tumour forms in the lowest portion of the brain. It can either be a low or a high grade tumour. Diffuse intrinsic pontine glioma is the most frequent type.

Risk Factors
• Ionizing radiation: Cell damage can be caused by Ionizing radiation from high-dose x-rays (such as radiation therapy from a big machine aimed at the head) leading to a tumour. Exposure to ionizing
   radiationmay increase brain tumour risk such as meningioma or glioma.
• Family history: Brain tumour running in family is rare. Rarely will you find families having many members suffering from brain tumour

Symptoms
A brain tumour symptoms depend on the size, type and location of the tumour. Symptoms can also be caused when a tumour exerts pressure on a nerve or harms a brain part. Another cause of the symptom be when the fluid flowing through and around the brain is blocked by a tumour, or when the fluid build-up causes the brain to swell.

The common most symptoms of brain tumours include:
• Headaches (generally worse in mornings)
• Vomiting & Nausea
• Alterations in speaking, seeing and hearing
• Balancing or walking problems
• Mood swings, change in personality or concentration abilities
• Memory problems
• Jerking or twitching of muscle (seizures or convulsions)
• Numbness or tingling in the arms or legs

Most often, brain tumour is not the cause of these symptoms. Another health problem could cause them. If you possess any of these symptoms, let your doctor have a look at it so that the issues can be diagnosed and treated.

Diagnosis:
If symptoms suggesting brain tumour is detected by your doctor, he will give you a physical exam and inquire about your personal and family health history. You may have to undergo one or more of the following tests:

• Neurologic exam: Your vision, hearing, alertness, muscle strength, coordination and reflexes are checked by your doctor. He also examines your to check for swelling caused by a tumour exerting
  pressure on the nerve connecting the eye & the brain.
• MRI: Detailed pictures of areas inside your head is made using a big machine with a powerful magnet linked to a computer. At times a special dye (contrast material) is injected into your hand or arm’s
  blood vessel to distinguish the tissues of the brain. Abnormal areas like tumour can be shown by these pictures.
• CT scan: A computer linked x-ray machine takes a series of detailed pictures of your head. A contrast material may be injected into a blood vessel in your arm or hand. It is easier to see abnormal areas
  because of the contrast material.
• Angiogram: By injecting dye into the bloodstream, blood vessels in the brain show up on an x-ray. If there is presence of a tumour, the x-ray may show the tumour or blood vessels feeding into the
  tumour.
• Spinal tap: A sample of cerebrospinal fluid may be removed by your doctor. Local anaesthesia is used in this procedure. The doctor makes use of a long, fine needle to remove fluid from the spinal
  column’s lower part. A spinal tap takes about half an hour. To prevent getting a headache you must lie flat for several hours following the procedure. The fluid is checked by a laboratory for cancer cells or
  other signs of problem.
• Biopsy: Removing of tissue to check for tumour cells is called biopsy. A pathologist examines cells under a microscope to look for abnormal cells. A biopsy can detect cancer, alteration in tissue that may
  lead to cancer and other conditions. A biopsy is the only definite means of diagnosing a brain tumour, find out what grade it is, and plan treatment.

The surgeon can acquire tissue to check for tumour cells in 2 ways:
• Simultaneous biopsy with treatment: The tissue sample is take when you have a surgery to remove a portion or the entire tumour.
• Stereotactic biopsy: A local or general anaesthesia may be administered to you and you’ll be made to wear a rigid head frame for this procedure. The surgeon creates a small incision in the scalp and after
  drilling a tiny hole (a burr hole) into the skull through which CT or MRI is guided to the tumour’s location. A sample of tissue is withdrawn with the needle. In case the tumour is deep inside the brain or in a
  region of the brain that cannot be operated on, a needle biopsy may be used.

But, if the tumour exists in the brain stem or certain other regions, the surgeon may not be able to acquire tissue from the tumour without harming normal tissue of brain. In such cases, MRI, CT or other imaging tests are used by doctors to acquire as much information as possible about brain tumour.

Treatment:
Individuals suffering from brain tumour have vast number of treatment options like surgery, radiation therapy and chemotherapy. A lot of people receive a combination of treatments. The treatment choice mainly depends on the following:
• Type of brain tumour and its grade.
• Tumour’s location in the brain
• Size of tumour
• Your age and general health

For certain types of brain cancer, the surgeon also needs to know if the cancer cells were detected in the cerebrospinal fluid.

i) Surgery
The usual first treatment for a majority of brain tumours is surgery. Prior to the commencement of surgery, general anaesthesia may be administered to you, and your scalp is shaved. You won’t probably need your head shaved entirely.
Craniotomy is a surgery to open the skull. An incision is made in your scalp and a special type of saw is used to remove a section of bone from the skull. You may be conscious when a part or all of the brain tumour is removed by the surgeon. The tumour is removed as much as possible. You may be asked to move a leg, count numbers, say the alphabet or recite a story. Your ability to follow these instruction helps the surgeon to protect the brain’s important parts.
After the removal of the tumour, the opening of the skull is covered with the piece of bone or with a metal or fabric piece. The incision in the scalp is then closed by the surgeon.
Sometimes, it isn’t possible to perform a surgery. But in case the tumour is in the brain stem or certain other areas, it is very complicated to remove the tumour without causing harm to normal brain tissue. Individuals who cannot have surgery may be given radiation therapy or other treatment.

ii) Radiation Therapy
Using high-energy x-rays, gamma rays, or protons brain tumour cells are killed by radiation therapy.
Following surgery comes radiation therapy. The tumour cells that may remain in the area is killed by the radiation. Sometimes, who can’t have surgery performed on them receive therapy instead.

Internal and external types of radiation therapy are used by doctors for treating brain tumours:

• External radiation therapy: You’ll receive treatment in a hospital or clinic. A big machine outside the body aims radiation beams at the head. The radiation may be aimed at the tumour and brain tissue
  nearby or the entire brain since cancer cells may invade normal tissue around a tumour. Some people require radiation aimed at the spinal cord too.
  The patient’s age, the type and size of the tumour determines the treatment protocol. The most common radiation treatment for brain tumour is fractionated external beam therapy. Here the total dose of
  radiation is given to the patient over several weeks helping to protect the healthy tissue in the area of the tumour. The treatments generally lasts 5 days a week for several weeks. Where each sitting takes
  around 1 hour.

Other ways of delivering external beam radiation are being studied by some treatment centres:
– Intensity-modulated radiation therapy or 3-dimensional conformal radiation therapy: computers are used by these type of treatment to target the brain tumour more closely in order to reduce the
  damage to healthy tissue.
– Proton beam radiation therapy: Instead of x-rays, the source of radiation here is protons. The proton beam is aimed at the tumour. Compared to the dose of radiation from an x-ray beam, the dose from
  a proton beam is less.

Stereotactic radiation therapy: Narrow beams of x-rays or gamma rays are directed at the tumor from different angles. For this procedure, you wear a rigid head frame. The therapy may be given during a single visit (stereotactic radiosurgery) or over several visits.

– Stereotactic radiation therapy: From different angles, narrow beams of x-rays or gamma rays are targeted at tumours from various angles. You are made to wear a rigid frame for this procedure. The
  therapy may be administered during one single visit (stereotactic radiosurgery) or over multiple visits.
– Internal radiation therapy (Implant radiation therapy or brachytherapy): Internal radiation is generally not used for brain tumours treatment and is under study. The radiation comes from radioactive
  material generally contained in very tiny implants known as seeds. The seeds are positioned in the inside of the brain and give off radiation for months. There is no need to remove them once the radiation
  is gone.

iii) Chemotherapy
Chemotherapy means making use of drugs for killing cancer cells. Many a times, Chemotherapy is used for treating brain tumours. Drugs can be administered in the following ways:

• By mouth or vein (intravenous): Chemotherapy can be administered during and after radiation therapy. After entering the bloodstream, the drugs travel throughout the body. They may be administered
  in the hospital’s outpatient part, at the doctor’s office, or at home. Seldom, you may require to stay in the hospital.
  Chemotherapy’s side effects depend chiefly on drugs which are given and the quantity of it. Common observed side effects are nausea and vomiting, appetite loss, headache, chills and fever, and weakness.
  If the levels of healthy blood cells are reduced by the drugs, you’re more prone to get infections, bruise or bleed easily, and experience tiredness and weakness. Your health care team would inspect for low
  levels of blood cells. Few of the side effects can be relieved with the help of medicine.

iv) Nutrition
You need to eat well in order to take good care of yourself. You require the correct amount of calories for maintaining a good weight. Also, you require sufficient protein to sustain your strength. Eating properly can go a long way in helping you feel better and have extra energy.

v) Supportive Care
Seizures (convulsions) cab be caused by brain tumours. Specific drugs can help in preventing or controlling seizures. You will receive supportive care before, during, and post cancer treatment. It will help in improving your comfort and quality of life during treatment.

vi) Rehabilitation
Rehabilitation is a very significant part of the treatment plan. Rehabilitation goals depend on your needs and the extent to which the tumour has affected your ability to perform daily activities.
Few individuals may never regain all the abilities possessed by them before the brain tumour and its treatment. But every effort is made by your healthcare team to help you get back to regular activities without delay.
Children suffering from brain tumours may have special requirements. Many times in the hospital or at home, children have tutors.

Several types of therapists can help:
• Physical therapists: Paralysis may be caused by brain tumours and their treatment. Weakness and problems with balance may also be caused by them. Physical therapists assist people in regaining
  strength and balance.
• Speech therapists: Individuals having trouble speaking, expressing thoughts, or swallowing are helped by speech therapists.
• Occupational therapists: Occupational therapists assist people in learning to accomplish activities of daily living, like eating, using the washroom, having bath, and dressing.
• Physical medicine specialists: Medical doctors with special training assist individuals with brain tumours to stay very active. They can assist individuals regain lost abilities and get back to daily activities.