A brain tumor is any abnormal growth or mass that develops in the skull space usually occupied exclusively by the brain. It may be noncancerous or malignant; both types of growths are potentially life threatening because they encroach on normal brain tissue, which, because of the surrounding skull, becomes compressed. Symptoms include severe or persistent headaches, personality changes, increased irritability and moodiness, unusual sleepiness, unexplained nausea and vomiting, paralysis, and balance problems. There may also be some deficits of the senses, including hearing, vision, speech, taste, and smell. The most common noncancerous type of brain tumor is called a meningioma, because it arises from the meninges, the thin membranes that cover the brain and the spinal cord. Of the primary brain cancers, gliomas are the most prevalent, accounting for about 45 percent of cases. Gliomas and other primary brain cancers seldom metastasize. Their rate of growth varies greatly; some may be present for years without causing any problems, while others are rapidly fatal. There has been a baffling increase in primary brain cancers in recent years, especially among children and young adults. The causes remain largely unknown, although some evidence points to environmental factors. The increase may be linked to a viral infection or possibly exposure to radiation or certain chemicals.
Diagnostic Studies and Procedures
Characteristic symptoms raise a suspicion of a brain tumor. The presence of one is confirmed by various imaging techniques-usually X-rays of the skull and CT scans or MRI. A biopsy of the tumor cells is necessary, however, to learn whether or not it is malignant.
Brain tumors are most often treated with radiation, surgery, or a combination of the two. In some cases, a surgeon can remove the entire tumor and effect a complete cure. Developments in computer assisted surgery, which now make it possible for surgeons to remove tumors deep within the brain, have increased the chances of surgical cure for some types of brain tumors. If a tumor is inoperable, if it recurs or metastizes, or if only part of it can be A brain tumor can often be found with a CT scan. On the left is a scan showing a normal brain. The one on the right reveals a glioma. removed, radiation is used. With a technique known as radiosurgery, high dose radiation can be beamed directly into the tumor to shrink it. In recent years, cancer specialists have also developed methods for using chemotherapy to treat brain cancer. A protective barrier prevents most drugs from penetrating the brain. But doctors can now administer doses directly into the brain via a small, implanted tube. Another promising experimental treatment involves implanting one or more polymer wafers about the size of a nickel into the brain. The wafer peels away like the skin of an onion over a period of a month, dispensing a powerful drug called BCNU. This system targets the drug directly to the brain over an extended period of time, without exposing other parts of the body to the toxic side effects.
Alternative therapies are unlikely to cure a brain tumor, but they can help relieve some of the symptoms.
This is often used to lessen cancer pain. It may be combined with chemotherapy and radiation as part of the overall treatment program.
Hypnosis and Imagery
These techniques also help cancer patients to control pain, as well as nausea and other unpleasant symptoms. Self hypnosis is now being taught to patients at many pain and cancer centers. The goal of guided imagery goes beyond pain control. While the patient relaxes in a trancelike state, a therapist or a tape recording instructs him to visualize the condition mentally and then to imagine ways of helping the immune system eradicate it. This technique requires patients to study and understand the body’s immune system, and then to visualize how it can over come the tumor. The efficacy of guided imagery has not been proven scientifically, but some researchers theorize that it may bolster the immune system by reducing stress and its effects.
Although self treatment of a brain tumor is not possible, working with speech and physical therapists during the recovery period after surgery can help to overcome some or all of the residual disability.
Other Causes of Brain Tumors
Most malignant brain tumors arise elsewhere in the body and then spread to the brain. Sometimes, a metastatic brain tumor is found before the primary cancer has been diagnosed. Thus, the discovery of a brain malignancy usually prompts a search for cancer in other parts of the body, especially the lungs, breasts, and bones, using imaging techniques similar to those employed in detecting a brain tumor.