Brain Tumor Treatment
Surgery is the usual treatment for most brain tumors. To remove a brain tumor, a neurosurgeon makes an opening in the skull. This operation is called a craniotomy. Whenever possible, the surgeon attempts to remove the entire tumor. If the tumor cannot be completely removed without damaging vital brain tissue, your doctor may remove as much of the tumor as possible. Partial removal helps to relieve symptoms by reducing pressure on the brain and reduces the amount of tumor to be treated by radiation therapy or chemotherapy.
Some tumors cannot be removed. In such cases, your doctor may do only a biopsy. A small piece of the tumor is removed so that a pathologist can examine it under a microscope to determine the type of cells it contains. This helps your doctor decide which treatment to use.
Sometimes, a biopsy is done with a needle. Doctors use a special head frame (like a halo) and CT scans or MRI to pinpoint the exact location of the tumor. The surgeon makes a small hole in the skull and then guides a needle to the tumor. Using this technique to do a biopsy or for treatment is called stereotaxis.
Other advanced techniques during surgery include brain mapping to find functional pathways near tumors, endoscopy to perform biopsies and open spinal fluid pathways through a small scope and advanced frameless stereotaxic computer assisted tumor resections. Intraoperative MRI also is available to help maximize tumor removal.
Radiation therapy may be given in two ways. External radiation comes from a large machine. Generally, external radiation treatments are given five days a week for several weeks. The treatment schedule depends on the type and size of the tumor and your age. Giving the total dose of radiation over an extended period helps to protect healthy tissue in the area of the tumor.
External radiation may be directed just to the tumor, the surrounding tissue or the entire brain. Sometimes the radiation is also directed to the spinal cord. When the whole brain is treated, the patient often receives an extra dose of radiation to the area of the tumor. This boost can come from external radiation or from an implant.
Radiation also can come from radioactive material placed directly in the tumor, or implant radiation therapy. Depending on the material used, the implant may be left in the brain for a short time or permanently. Implants lose a little radioactivity each day. The patient stays in the hospital for several days while the radiation is most active.
The Gamma Knife, or stereotactic radiosurgery, is another way to treat brain tumors. The Gamma Knife isn't actually a knife, but a radiation therapy technique that delivers a single, finely focused, high dose of radiation precisely to its target. Treatment is given in just one session. High-energy rays are aimed at the tumor from many angles. In this way, a high dose of radiation reaches the tumor without damaging other brain tissue.
Chemotherapy is the use of drugs to kill cancer cells. The doctor may use just one drug or a combination, usually giving the drugs orally or by injection into a blood vessel or muscle. Intrathecal chemotherapy involves injecting the drugs into the cerebrospinal fluid.
Chemotherapy is usually given in cycles. A treatment period is followed by a recovery period, then another treatment period and so on. Patients often don't need to stay in the hospital for treatment and most drugs can be given in the doctor's office or clinic. However, depending on the drugs used, the way they are given and the patient's general health, a short hospital stay may be necessary.
Advances in chemotherapy include direct placement into the tumor cavity using a new technique called convection enhanced delivery.