Brain Tumor : Overview, Symptoms, and Causes

Overview

A brain tumor is a mass or growth of abnormal cells in your brain. Many different types of brain tumors exist. Some brain tumors are noncancerous (benign), and some brain tumors are cancerous (malignant). Brain tumors can begin in your brain (primary brain tumors), or cancer can begin in other parts of your body and spread to your brain (secondary, or metastatic brain tumors).

The number of brain tumors diagnosed each year is increasing. There’s evidence the increase has been occurring for decades. But it’s not clear why.

Sypmtoms

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

General signs and symptoms caused by brain tumors may include:

• New onset or change in pattern of headaches
• Headaches that gradually become more frequent and more severe
• Unexplained nausea or vomiting
• Vision problems, such as blurred vision, double vision or loss of peripheral vision
• Gradual loss of sensation or movement in an arm or a leg
• Difficulty with balance
• Speech difficulties
• Confusion in everyday matters
• Personality or behavior changes
• Seizures, especially in someone who doesn’t have a history of seizures
• Hearing problems
• Hormonal (endocrine) disorders

Causes

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

Primary brain tumors are much less common than are secondary brain tumors, in which cancer begins elsewhere and spreads to the brain. Many different types of primary brain tumors exist. Each gets its name from the type of cells involved. Examples include:

• Acoustic neuroma (schwannoma)
• Astrocytoma, also known as glioma, which includes anaplastic astrocytoma and glioblastoma
• Ependymoma
• Ependymoblastoma
• Medulloblastoma
• Meningioma
• Neuroblastoma
• Oligodendroglioma
• Pineoblastoma

Cancer that begins elsewhere and spreads to the brain
Secondary (metastatic) brain tumors are tumors that result from cancer that starts elsewhere in your body and then spreads (metastasizes) to your brain. In some cases you may have a history of cancer when a brain tumor is discovered. In other cases, a brain tumor is the first sign of cancer that began elsewhere in your body.

Secondary brain tumors are far more common than are primary brain tumors. Any cancer can spread to the brain, but the most common ones include:

• Breast cancer
• Colon cancer
• Kidney cancer
• Lung cancer
• Melanoma
• Neuroblastoma
• Sarcoma

Taken from: http://www.mayoclinic.com/health/brain-tumor/DS00281