Chemotherapy is the form of therapy that uses drugs to kill cancer cells. The drugs enter the bloodstream or directly into the fluid of the brain (cerebrospinal fluid) and travel through the body in order to kill cancer cells. The side effects from the chemotherapy come from the fact that it destroys normal cells as well.
Chemotherapy may be given either alone or along with radiation therapy. When given alone, it is given in a higher dose designed to kill off cancer cells. When given along with radiation therapy it is delivered at a lower dose, and is designed to make the cancer more sensitive to the radiation.
Chemotherapy is usually given by vein, but some forms can be given by mouth, as well. For brain tumors, chemotherapy may also be given directly into the meninges of the brain and spinal cord. This is called intrathecal chemotherapy. Your medical oncologist will tell you how many cycles or courses of chemotherapy are best for you. Usually there are between 4-6 cycles of chemotherapy given when the chemotherapy is delivered on its own, and up to 10 cycles of chemotherapy when the drugs are given along with the radiation therapy.
The side effects and amount of time required in the doctor’s office depend on the type of chemotherapy you receive, as well as how many cycles you receive and how often. The most common chemotherapy-associated side effects are:
- Nausea and vomiting
- Fatigue or tiredness
- Hair loss
- Increased swelling in the brain which can cause dizziness, blurred vision, weakness, seizures, loss of bowel and bladder control
When chemotherapy is given at a lower dose, as when it is given along with radiation, these side effects are less common. However, most people still feel very fatigued.
