Chemotherapy (also known as "chemo") uses anti-cancer drugs that are usually given into a vein (IV) or taken by mouth. These drugs enter the bloodstream and reach almost all areas of the body. However, because of the blood-brain barrier (see “What are brain and spinal cord tumors in adults?”), many chemotherapy drugs are not able to enter the brain and reach tumor cells.
For some brain tumors, the drugs may be given directly into the cerebrospinal fluid (CSF), either in the brain or into the spinal canal below the spinal cord. To help with this, a thin tube, known as a ventricular access catheter, may be inserted through a small hole in the skull and into a ventricle of the brain during a minor operation (see the "Surgery" section).
In general, chemotherapy is used for higher grade tumors. Some types of brain tumors, such as medulloblastoma and lymphoma, tend to respond better to chemotherapy.
Chemotherapy is most often used along with other types of treatment such as surgery and/or radiation therapy. Chemotherapy may also be used by itself, especially for more advanced tumors or for tumors that have come back after other types of treatment.
Some of the chemotherapy drugs that may be used to treat brain tumors include:
- Carmustine (BCNU)
- Lomustine (CCNU)
- Temozolomide
- Carboplatin
- Cisplatin
- Etoposide
- Irinotecan
- Methotrexate
- Procarbazine
- Vincristine
These drugs may be used alone or in various combinations, depending on the type of brain tumor. Doctors give chemotherapy in cycles, with each period of treatment followed by a rest period to give the body time to recover. Each chemotherapy cycle typically lasts for a few weeks.
Carmustine (Gliadel®) wafers
These dissolvable wafers contain the chemotherapy drug carmustine (BCNU). During a craniotomy, they can be placed directly on or next to parts of brain tumors that can't be removed. Unlike IV or oral chemotherapy that reaches all areas of the body, this type of therapy increases the drug concentration at the tumor site with minimal side effects in other parts of the body.
Possible side effects of chemotherapy
Chemotherapy drugs attack cells that are dividing quickly, which is why they often work against cancer cells. But other cells, such as those in the bone marrow, the lining of the mouth and intestines, and the hair follicles, also divide quickly. These cells are also likely to be affected by chemotherapy, which can lead to side effects.
The side effects of chemotherapy depend on the type of drugs, the amount taken, and the length of treatment. Possible side effects can include:
- Hair loss
- Mouth sores
- Loss of appetite
- Nausea and vomiting
- Diarrhea
- Increased chance of infections (due to low white blood cell counts)
- Easy bruising or bleeding (due to low blood platelet counts)
- Fatigue (due to low red blood cell counts, changes in metabolism, or other factors)
Fortunately, some of the most effective drugs against brain tumors tend to have fewer of these side effects than other common chemotherapy drugs, but they are still possible. These side effects are usually short-term and go away after treatment is finished. There are often ways to lessen these side effects. For example, drugs can be given to help prevent or reduce nausea and vomiting.
Along with the risks above, some chemotherapy drugs can cause other, less common side effects. For example, cisplatin and carboplatin can also cause kidney damage and hearing loss. Your doctor will check your kidney function and hearing if you are given these drugs. Some of these side effects may persist after treatment is stopped.
You should report any side effects you notice while getting chemotherapy to your medical team so that you can be treated promptly. In some cases, the doses of the chemotherapy drugs may need to be reduced or treatment may need to be delayed or stopped to prevent the effects from getting worse.
For more information on chemotherapy, see our document, Understanding Chemotherapy: A Guide for Patients and Families.
Feedback
