disease

brain tumor

Brain tumor is an abnormal growth of tissue in the brain. Unlike other tumors, brain tumors spread by local extension and rarely metastasize outside the brain. A benign brain tumor is composed of non-cancerous cells and does not metastasize beyond the part of the brain where it originates. A brain tumor is considered malignant if it contains cancer cells, or if it is composed of harmless cells located in an area where it suppresses one or more vital functions. Each year, more than 17,000 brain tumors are diagnosed in the United States. About half of all primary brain tumors are benign, but in life-threatening locations. The rest are malignant and invasive.

causes and risk factors:

No one knows the exactcauses of brain tumors. It is clear that brain tumors are not contagious. Research has shown that people with certain risk factors are more likely than others to develo a brain tumor.

The following risk factors are associated with an increased chance of developing a primary brain tumor:

• Being male - In general, brain tumors are more common in males than females.
• Race - Brain tumors occur more often among white people than among people of other races.
• Age - Most brain tumors are detected in people who are 70 years old or older. However, brain tumors are the second most common cancer in children. Brain tumors are more common in children younger than 8 years old than in older children.
• Family history - People with family members who have gliomas may be more likely to develop this disease. 
• Radiation - Workers in the nuclear industry have an increased risk of developing a brain tumor.
• Formaldehyde - Pathologists and embalmers who work with formaldehyde have an increased risk of developing brain cancer. Scientists have not found an increased risk of brain cancer among other types of workers exposed to formaldehyde.
• Vinyl chloride - Workers who make plastics may be exposed to vinyl chloride. This chemical may increase the risk of brain tumors.
• Acrylonitrile - People who make textiles and plastics may be exposed to acrylonitrile. This exposure may increase the risk of brain cancer.
• cell phones-  Scientists are investigating whether cell phones may cause brain tumors. Studies thus far have not found an increased risk of brain tumors among people who use cell phones.

symptoms:

• Headaches 
• Nausea or vomiting
• Changes in speech, vision, or hearing
• Problems balancing or walking
• Changes in mood, personality, or ability to concentrate
• Problems with memory
• Muscle jerking or twitching
• Numbness or tingling in the arms or legs

diagnoses of brain tumors:

• Physical exam - The doctor checks general signs of health.
• Neurologic exam - The doctor checks for alertness, muscle strength, coordination, reflexes, and response to pain. The doctor also examines the eyes to look for swelling caused by a tumor pressing on the nerve that connects the eye and brain.
• CT scan - An x-ray machine linked to a computer takes a series of detailed pictures of the head. The patient may receive an injection of a special dye so the brain shows up clearly in the pictures. The pictures can show tumors in the brain.
• MRI - A powerful magnet linked to a computer makes detailed pictures of areas inside the body. These pictures are viewed on a monitor and can also be printed. Sometimes a special dye is injected to help show differences in the tissues of the brain. The pictures can show a tumor or other problem in the brain.
• Angiogram - Dye injected into the bloodstream flows into the blood vessels in the brain to make them show up on an x-ray. If a tumor is present, the doctor may be able to see it on the x-ray.
• Skull x-ray - Some types of brain tumors cause calcium deposits in the brain or changes in the bones of the skull. With an x-ray, the doctor can check for these changes.
• Spinal tap - The doctor may remove a sample of cerebrospinal fluid. This procedure is performed with local anesthesia. The doctor uses a long, thin needle to remove fluid from the spinal column. A spinal tap takes about 30 minutes. The patient must lie flat for several hours afterward to keep from getting a headache. A laboratory checks the fluid for cancer cells or other signs of problems.
• Myelogram - This is an x-ray of the spine. A spinal tap is performed to inject a special dye into the cerebrospinal fluid. The patient is tilted to allow the dye to mix with the fluid. This test helps the doctor detect a tumor in the spinal cord.
• Biopsy - The removal of tissue to look for tumor cells is called a biopsy. A pathologist looks at the cells under a microscope to check for abnormal cells. A biopsy can show cancer, tissue changes that may lead to cancer, and other conditions. A biopsy is the only sure way to diagnose a brain tumor. 

methods of treatment: 


There are several treatment options depending on the tumor type and stage, patients may be treated with surgery, radiation therapy, or chemotherapy.
Surgery is the usual treatment for most brain tumors. It is performed under general anesthesia. The surgeon then makes an incision in the scalp and uses a special type of saw to remove a piece of bone from the skull. After removing part or all of the tumor, the surgeon covers the opening in the skull with that piece of bone or with a piece of metal or fabric. The surgeon then closes the incision in the scalp.
Radiation therapy
It uses high-energy rays to kill tumor cells. The radiation may come from x-rays, gamma rays, or protons. A large machine aims radiation at the tumor and the tissue close to it. Sometimes the radiation may be directed to the entire brain or to the spinal cord. The radiation kills tumor cells that may remain in the area.
Fractionation - Radiation therapy usually is given five days a week for several weeks. Giving the total dose of radiation over an extended period helps to protect healthy tissue in the area of the tumor. Hyperfractionation - The patient gets smaller doses of radiation two or three times a day instead of a larger amount once a day.
Stereotactic radiation therapy - Narrow beams of radiation are directed at the tumor from different angles. For this procedure, the patient wears a rigid head frame. The therapy may be given during a single visit or over several visits.
Chemotherapy
The use of drugs to kill cancer cells, is sometimes used to treat brain tumors. The drugs may be given by mouth or by injection. Either way, the drugs enter the bloodstream and travel throughout the body. 
For some patients with recurrent cancer of the brain, the surgeon removes the tumor and implants several wafers that contain chemotherapy. Each wafer is about the size of a dime. Over several weeks, the wafers dissolve, releasing the drug into the brain.

after treatment:

Regular followup is very important after treatment for a brain tumor. The doctor checks closely to make sure that the tumor has not returned. Checkups may include careful physical and neurologic exams. From time to time, the patient may have MRI or CT scans.