Chemotherapy to Treat Brain Cancer
Generally, brain tumors are treated with radiation and/or surgery. Chemotherapy is not used for benign tumors, but this treatment might be used for malignant primary brain tumors or metastatic tumors.
The problem with chemotherapy is that it works by interrupting mitosis, the process of cell division. Many brain tumors grow slowly by nature, so slowing their growth by chemotherapy doesn't do much good. Another problem with chemotherapy is that not all chemical agents can cross the blood-brain barrier and get to the tumor.
The capillaries and arteries in the central nervous system are unlike the vessel walls found in the rest of the body, which allow proteins and large organic molecules to pass out of the bloodstream and into tissues. Vessel walls in the CNS allow only water, small solutes, and simple gases such as oxygen and carbon dioxide to pass into brain tissue. While this protects the brain from exposure to chemical flux in the body, it also creates a barrier against many therapeutic agents, making chemotherapy problematic.
Chemotherapy uses chemicals that are designed to poison tumor cells, but it's difficult to know which chemicals will reach which tumors. So, a combination of chemicals is usually used to treat a brain tumor.
Some cancer cases require chemotherapy after surgery and radiation. Chemotherapy is also used as a radio-sensitizing agent with radiation to control a recurrent tumor and to treat patients who can no longer tolerate radiation therapy.
Overall, studies have shown that patients who receive chemotherapy for malignant tumors have improved survival rates compared to patients who do not. The effectiveness of chemotherapy depends on the tumor type (medulloblastomas, anaplastic astrocytomas, and glioblastomas respond in varying degrees).
Chemotherapy is often used in very young children to delay radiation therapy for as long as possible. Some meningiomas respond to antiprogesterone agents. Most mestastatic brain tumors do not respond to chemotherapy, although there are exceptions. For these, the best chemotherapy agent is usually the one that has been the most effective with the primary cancer.
Agents that commonly work in patients with high-grade gliomas include procarbazine, platinum analogs (cisplatin, carboplatin), the nitrosureas, and an oral medication called Temodar® (temozolomide). In March 2009, the U.S. Food and Drug Administration (FDA) approved an intravenous (IV) form of temozolomide.
One chemotherapeutic agent that has proved to be effective is BCNU. The neurosurgeon places a wafer soaked with BCNU (Gliadel®, BiCNU®) into the surgical cavity after the tumor has been removed. By applying it directly to the diseased area of the brain, side effects are limited and the drug has a more beneficial effect.
Chemotherapy agents being tested for use in recurrent glial tumors include Taxol (paclitaxel), irinotecan, topotecan, and high-dose tamoxifen with either carboplatin or procarbazine. Other chemotherapeutic agents for the treatment of recurrent gliomas include interferon and retinoic acid.
There are many experimental treatments, ranging from novel chemotherapeutic agents to drug therapy to new ways of applying radiation, that your neurologist, neurosurgeon, radiation oncologist or neuro-oncologist can discuss with you. As with any serious illness, it is generally a good idea to understand your options, get a second or third opinion, and gather as much information as you can about your particular case.
Other Treatments for Brain Cancer
An assortment of other treatments are commonly used when a brain tumor fails to respond to surgery, radiation, or chemotherapy. These involve the use of angiogenesis inhibitorsdrugs that disrupt the blood vessels in a tumor, thereby cutting off a tumor's supply of nutrients and oxygen; differentiating agentsdrugs that convert dividing cancer cells into mature, nondividing cells, thereby stopping further tumor growth; immunotherapyvarious techniques that attempt to boost a person's immune system so that it more effectively fights the tumor cells; and gene therapyinserting genes into tumor cells or the immune system to change the way the tumor cells operate.
In 2011, the U.S. Food and Drug Administration (FDA) approved a new device to treat adults with a type of brain cancer (glioblastoma multiforme [GBM]) that recurs following treatment with radiation therapy and chemotherapy. In this treatment, electrodes are placed on the scal[ to deliver low-intensity electrical fields to the tumor. These electrical fields, which are referred to as tumor treatment fields, may help stop the growth of the tumor.
The device is portable and allows patients to continue with daily activities. This treatment may increase the risk for neurological side effects (e.g., headaches, convulsions), but does not cause side effects associated with chemotherapy, such as nausea, fatigue and infections. Overall survival rates are similar to chemotherapy.
Rehabilitation and Brain Cancer Treatment
Because of the effect that a brain tumor or treatment has on how a person functions, rehabilitation is an important part of recovery. Occupational rehabilitation involves restoring normal daily functioning, from working with one's hands to driving. Physical therapy involves improving a strength and motor function. Speech and language therapy may be important for restoring the ability to speak clearly. Cognitive therapy may be important for helping one deal with short-term memory loss.
There are specialists available to help with vision, balance, or facial paralysis problems. Sometimes patients need vocational therapy to help them return to the working world.
Self-help for Brain Cancer Patients
It is a good idea to look for a support group and/or a counselor or psychotherapist to help deal with the stress and emotional challenges of living with, and recovering from, a brain tumor. Maintaining a positive attitude and taking care of one's emotional well-being are very important. It is important to exercise and a establish a healthy diet in order to feel well.