Brain Tumor, Brain Cancer

A brain tumor is a disease in which cells grow uncontrollably in the brain. Cancer occurs when cells in the body divide without control or order. If cells divide uncontrollably they form a mass of tissue. The mass is called a growth or tumor. The term cancer usually refers to malignant tumors. These can invade nearby tissue and can spread to other parts of the body. A benign tumor does not spread, but it can continue to grow and press structures near it, causing symptoms.

There are two main types of brain tumors:

• Primary brain cancer—This begins in the brain. It can be either malignant or benign. A small benign tumor in a bad location can cause significant problems.
• Secondary or metastatic brain cancer—This has spread to the brain from another site in the body. All metastatic tumors are malignant.

Brain Tumor

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The cause of most primary brain cancer is unknown. The causes of secondary brain cancers are those that caused the cancer at the site of origin.

Risk Factors

These factors increase your chance of developing brain tumors:

• Radiation
• Immune system dysfunction
• Family history of certain types of cancer

Any cancer throughout the body can spread to the brain. The following is a list of the most common tumors that may spread to the brain at some point:

• Lung cancer
• Breast cancer
• Malignant melanomas
• Gastrointestinal tract cancer
• Kidney cancer

Symptoms

Symptoms depend on the tumor's size and location. A growing tumor will often have surrounding fluid build-up, called edema. Edema puts pressure on the brain. Symptoms may develop gradually or rapidly.

Symptoms may include:

• Headache—Most headaches are not caused by brain tumors. Headaches due to brain tumors tend to have the following features:
  • Progressively worse over a period of weeks to months
  • Worse in the morning or cause you to wake during the night
  • Different than a normal headache
  • Worsens with change of posture, straining, or coughing
• Seizures
• Nausea or vomiting
• Weakness in arms and/or legs
• Loss of sensation in arms and/or legs
• Difficulty walking
• Hearing loss or vision loss (including double vision)
• Speech problems
• Drowsiness
• Memory problems
• Personality changes

These symptoms may also be caused by other, less serious conditions. If you have any of these symptoms, see your doctor.

Diagnosis

The doctor will ask about symptoms and medical history. A physical exam will be done. You will have a neurological exam. It will test muscle strength, coordination, reflexes, response to stimuli, and alertness. The doctor may also look into your eyes to check for signs of brain swelling.

Tests may include:

• MRI scan —a test that uses magnetic waves to make pictures of structures inside the body
• CT scan —a type of x-ray that uses a computer to make pictures of structures inside the body
• PET scan —a test that detects levels of metabolic activity by tracking a radioactive sugar molecule
• Combination PET and CT scan (PET/CT scan)
• Single-photon emission computed tomography (SPECT)—an test that uses gamma rays to create images
• Arteriography —a test that uses x-rays to make pictures of blood vessels in the brain
• Biopsy —removal of a sample of brain tissue to test for cancer cells; may involve a small needle being inserted into the brain or surgery
• Stereotaxis—use of a computer-assisted CT or MRI scan to locate the tumor and take a biopsy

There are many different types of brain tumors. The doctor will classify the type. The type of brain tumor is important in determining the treatment approach.

Treatment

Once cancer is found, further tests may be done if there is concern that the cancer has spread. Treatment depends on the type, size, and location of the cancer, and your overall health. Treatments may leave you with physical or mental limitations.

Before beginning treatment, you may take medicines, including:

• Steroids to decrease swelling and fluid buildup
• Anticonvulsants to prevent seizures

Surgery

Surgical procedures include:

• Craniotomy —opening the skull to remove the tumor or as much of the tumor as possible
• Shunt—implanting a long thin tube in the brain to divert built-up fluid to another part of the body

Radiation Therapy

The use of radiation to kill cancer cells and shrink tumors. This is a common treatment for brain tumors. Radiation may be:

• External radiation therapy—Radiation is directed at the tumor from a source outside the body. If you have a metastatic brain tumor, you will receive whole brain radiation therapy (WBRT). If you have a primary brain tumor, you will receive more focused radiation therapy. WRBT may also be used in people who have cancer in other areas of the body. The treatment is used to prevent brain cancer.
• Internal radiation therapy—Radioactive materials placed into the body near the cancer cells. This is used less often.
• Stereotactic radiosurgery —Higher doses can be delivered to the affected areas of the brain. Nearby normal tissue can be spared. Special equipment, including MRI and CT scans, help to localize the delivery of the radiation. This is most often used in metastatic brain tumors or in benign brain tumors, such as meningiomas.

Chemotherapy

Chemotherapy is the use of drugs to kill cancer cells. It may be given in many forms, including pill, injection, and via a catheter. The drugs enter the bloodstream and travel through the body killing mostly cancer cells, but also some healthy cells. It may also be delivered directly into the cerebrospinal fluid, which bathes the brain tissue. This form of chemotherapy is called intrathecal. This is most often used when there is spread of cancer from elsewhere in the body to the fluid surrounding the brain and spinal cord.

Rehabilitation Therapy

Rehabilitation therapy includes:

• Physical therapy to help with walking, balance, and building strength
• Occupational therapy to help with mastering life skills, such as dressing, eating, and using the toilet
• Speech therapy to help express thoughts and overcome swallowing difficulties

Prevention

There are no guidelines for preventing brain cancer.

At present, there is no conclusive evidence that using cell phones or living by electrical wires or power plants increases your risk of developing a brain tumor.