What are the current treatments available for malignant brain tumors?

The successful treatment of malignant brain tumors, remains one of the most difficult problems in medicine. Conventional treatments such as surgery and radiation treatments are often effective ways of causing a tumor remission but rarely result in cure or even a long survival. As a result, a wide variety of experimental therapies are available and should be considered as part of tumor management.

Surgery
Recent advances in computer guidance systems (“frameless stereotaxy”) have expanded the scope of tumors that are operable while allowing minimally invasive techniques using smaller incisions and resulting in fewer wound complications. Surgery for malignant brain tumors is most beneficial when the vast majority of the tumor can be removed, but even then it is almost never curative. “Debulking” a tumor refers to removing only a part of the mass of a tumor to help relieve pressure on the brain, when more radical tumor removal is considered unsafe, or when tumor tissue is needed to generate a brain tumor vaccine (see below).

• Radiation
  Radiation treatments remain one of the most effective means of getting a brain tumor into remission. Treatments are typically given daily for several weeks with the aim of killing most of the tumor cells in the treatment area (“Port”) while sparing most of the healthy brain cell. Certain types of tumors, such as those of the brainstem, respond better, if the treatment is given twice a day. (“Hyperfractionated radiotherapy”) Radioactive “Seeds” can also be surgically implanted into some malignant tumors, allowing a higher dose to be given to the tumor than by conventional techniques. Focused radiation that acts like an X–ray laser (photon knife or Gamma Knife) can be used to treat some benign and malignant tumors without conventional surgery. This technique is particularly effective for some tumors that spread to the brain from cancers elsewhere in the body; and may eliminate the need for conventional radiation treatments in some cases. Techniques to enhance the sensitivity of tumor cells to radiation; such as boron neutron capture, should in theory be more effective than conventional radiation treatments. This however has failed to provide much benefit. Experimental refinements may lead to better outcomes from this approach, down the road.
• Chemotherapy
  Although some malignant brain tumors are very sensitive to chemotherapy, the most common types of tumor are often resistant to conventional drug treatments. New approaches to treating such tumors include giving the chemotherapy before the patient undergoes radiation treatments, using extremely high doses of chemotherapy and direct injection of tumor–fighting drugs into the tumor at surgery.
• Immunotherapy
  One of the most exciting prospects in brain tumor treatment today is to use the patient’s own immune system to fight the tumor. By using bits of the patient’s tumor and special processing, a brain tumor vaccine can be created. This approach has been shown to cure brain tumors in animal studies and is just now beginning its first experimental trials in people with certain malignant brain tumors.
• Gene Therapy
  As brain cancers arise from abnormal DNA, it is hoped that one day it may be possible to fix the DNA and thereby kill these tumors. Early experience with gene therapy has had only limited success yet remains an area of hope for the future.

Brain Tumors in Children

My neighbor’s 5–year–old daughter has a brain tumor. I’m reluctant to ask questions about it, but my own kids are curious. What causes brain tumors? How likely is it she will be cured?

Tell your children that although the little girl is sick and will have to undergo a lot of therapy, there is a good chance she will be successfully treated. The likelihood of survival depends on many factors, but almost 60 percent of children survive the illness.

Brain tumors are the second most common form of cancer in children. There are many different kinds of brain tumors, and the type of treatment depends on the type of tumor, its extent and location. Some types of malignant tumors can often be successfully treated, while some benign tumors are resistant to all treatment.

We don’t know exactly what causes brain tumors; there are probably many factors. Scientists who investigate the causes of disease (epidemiologists) are investigating many possibilities including chemical and electromagnetic “Pollution”, although there are no known definite causes. There are three basic approaches to treating brain tumors, and a patient may require different combinations of each. Neurosurgery is usually essential to determine the kind of tumor. During the operation, the surgeon will attempt to remove all visible tumor tissue. Many patients will also require radiation and/or chemotherapy treatments after surgery to eradicate any remaining tumor cells that might multiply and form another tumor.

Radiation therapy is generally given in 20 to 30 treatments over a 4–to–6 week interval. Chemotherapy is given in specified cycles spread over a year. Both therapies have side effects, and neither is considered better or more effective than the other.

Your neighbor may not wish to discuss her daughter’s illness, but you or your children need not avoid them if they are friends. A tumor operation and subsequent therapy will consume a lot of your neighbor’s time. You might want to offer to help out by baby–sitting, driving children to school and running errands.