Surgery, radiation therapy, and chemotherapy all may be employed in the treatment of a brain tumor. Surgery is almost always needed toestablish the particular cell type of the tumor and to achieve a cure or as much relief of symptoms as possible. This may be followed by radiationtherapy or chemotherapy.
To gain access to and operate on the brain, it is necessary to remove a ‘ portion of the skull. Since the scar is usually placed under the hairline or ‘ in an unobtrusive place and the bone flap is returned to its original site and wired firmly to the adjacent bone, the final appearance of most patients after surgery is unaffected.
The total length of time required for the operation is four to eight hours, depending on the complexity of the procedure. Although CT scans and other tests reveal a good deal about the brain, the neurosurgeon does not know exactly what to expect before the actual operation. In about 15 percent of patients, the tumor will be a metastasis from elsewhere in the body. How much of the growth can be removed without unacceptable damage to nearby structures can be determined only at the time of the operation. Areas of the brain that control speech, vision, and movement are more important for a satisfactory postoperative quality of life than the “silent” areas of the frontal lobes. There is still a degree of unpredictability in some tumors as to what the postoperative result will be. If total removal is impossible, the neurosurgeon will still remove as much of the tumor as possible. Removal of even a small amount of tumor can greatly improve a patient’s quality and length of life because of relief of the mass effect. Reduction of pressure within the skull also gives the treatment team valuable time in which to plan additional approaches to treatment.
Some benign tumors, such as meningiomas, can be cured only by total surgical removal. If this is impossible, partial removal is nonetheless greatly beneficial and a repeat procedure can be attempted later to reduce the bulk of the tumor again.
Surgeons also perform shunting procedures to divert the flow of cerebrospinal fluid from blocked pathways. The goal of shunting and decompression may be short-term relief of pressure or long-term control of symptoms. Sometimes the coverings of the brain are simply left open beneath the skull and scalp to let the fluid travel elsewhere in the body. If long-term survival is expected, tubes may be implanted to shunt the fluid from the cerebral ventricles to locations such as the abdominal or chest cavities. Shunting by tiny pumps placed near the body surface and activated by finger pressure is also performed. The technique of shunting has been of great benefit especially in children born with congenital defects that cause hydrocephalus. There are potential complications, such as blockage and infection, but neurosurgeons have become adept at dealing with them. Shunt replacement is a common procedure in any large neurosurgical unit.