Brain tumours Symptoms and causes

  Symptoms and causes

Ø   Symptoms

The signs and symptoms of a brain tumour vary greatly and depend on the brain tumour's size, location and rate of growth.

General signs and symptoms caused by brain tumours may include:

1)        New onset or change in pattern of headaches

2)        Headaches that gradually become more frequent and more severe

3)        Unexplained nausea or vomiting

4)        Vision problems, such as blurred vision, double vision or loss of peripheral vision

5)        Gradual loss of sensation or movement in an arm or a leg

6)        Difficulty with balance

7)        Speech difficulties

8)        Confusion in everyday matters

9)        Personality or behavior changes

10)     Seizures, especially in someone who doesn't have a history of seizures

11)     Hearing problems

o  When to see a doctor

Make an appointment with your doctor if you have persistent signs and symptoms that concern you.

Ø  Causes

Ø  Malignant glioma cells

Ø  Acoustic neuroma (schwannoma)

o   Brain tumours that begin in the brain

Primary brain tumors originate in the brain itself or in tissues close to it, such as in the brain-covering membranes (meninges), cranial nerves, pituitary gland or pineal gland.

Primary brain tumours begin when normal cells acquire errors (mutations) in their DNA. These mutations allow cells to grow and divide at increased rates and to continue living when healthy cells would die. The result is a mass of abnormal cells, which forms a tumour.

Primary brain tumours are much less common than are secondary brain tumours, in which cancer begins elsewhere and spreads to the brain.

Many different types of primary brain tumours exist. Each gets its name from the type of cells involved. Examples include:

Ø  Gliomas. These tumours begin in the brain or spinal cord and include astrocytomas, ependymoma, glioblastomas, oligoastrocytomas and oligodendrogliomas.

Ø  Meningiomas. A meningioma is a tumour that arises from the membranes that surround your brain and spinal cord (meninges). Most meningiomas are noncancerous.

Ø  Acoustic neuromas (schwannomas). These are benign tumours that develop on the nerves that control balance and hearing leading from your inner ear to your brain.

Ø  Pituitary adenomas. These are mostly benign tumours that develop in the pituitary gland at the base of the brain. These tumours can affect the pituitary hormones with effects throughout the body.

Ø  Medulloblastomas. These are the most common cancerous brain tumours in children. A medulloblastomas starts in the lower back part of the brain and tends to spread through the spinal fluid. These tumours are less common in adults, but they do occur.

Ø  PNETs. Primitive neuroectodermal tumours (PNETs) are rare, cancerous tumours that start in embryonic (fetal) cells in the brain. They can occur anywhere in the brain.

Ø  Germ cell tumours. Germ cell tumours may develop during childhood where the testicles or ovaries will form. But sometimes germ cell tumours move to other parts of the body, such as the brain.

Ø  Craniopharyngiomas. These rare, noncancerous tumours start near the brain's pituitary gland, which secretes hormones that control many body functions. As the craniopharyngioma slowly grows, it can affect the pituitary gland and other structures near the brain.

o   Cancer that begins elsewhere and spreads to the brain

Secondary (metastatic) brain tumours are tumours that result from cancer that starts elsewhere in your body and then spreads (metastasises) to your brain.

Secondary brain tumours most often occur in people who have a history of cancer. But in rare cases, a metastatic brain tumour may be the first sign of cancer that began elsewhere in your body.

Secondary brain tumours are far more common than are primary brain tumours.

Any cancer can spread to the brain, but the most common types include:

1)        Breast cancer

2)        Colon cancer

3)        Kidney cancer

4)        Lung cancer

5)        Melanoma

o   Risk factors

In most people with primary brain tumours, the cause of the tumour is not clear. But doctors have identified some factors that may increase your risk of a brain tumour. Risk factors include:

Ø  Your age. Your risk of a brain tumour increases as you age. Brain tumours are most common in older adults. However, a brain tumour can occur at any age. And certain types of brain tumours occur almost exclusively in children.

Ø  Exposure to radiation. People who have been exposed to a type of radiation called ionising radiation have an increased risk of brain tumour. Examples of ionising radiation include radiation therapy used to treat cancer and radiation exposure caused by atomic bombs.

More common forms of radiation, such as electromagnetic fields from power lines and radio frequency radiation from cellphones and microwave ovens, have not been proved to be linked to brain tumours.

Ø  Family history of brain tumours. A small portion of brain tumours occur in people with a family history of brain tumours or a family history of genetic syndromes that increase the risk of brain tumours.