What is it?
Chemotherapy is any type of drug that works to kill tumor cells or prevent tumors from growing. Most effective against fast growing cells such as those seen in brain cancers, it can also act on fast growing cells that are normally present in your body. This can lead to hair loss, loss of taste, nausea, vomiting and diarrhea.
Blood cells are particularly susceptible to the effects of chemotherapy. For this reason, you doctors will ask that you get a blood test every week while you are taking chemotherapy.
Will you need it?
Depending on the type of tumor you have, chemotherapy may be part of your treatment plan. Previously, chemotherapy has not been very effective against brain tumors. The brain is protected by the blood brain barrier which has prevented many drugs from entering and acting against tumors. In recent years however, scientific research has led to the discovery of chemotherapies that can get through this barrier in order to work against brain tumors.
What types of chemotherapy do we use?
The chemotherapy that we use most commonly in brain tumors is called temozolomide (Temodar®). It works by killing the rapidly growing cells in the tumor and slowing tumor growth. It comes as a capsule and can be taken at home. In addition to lowering blood counts, the most common side effects to Temodar® are nausea, vomiting, constipation and headaches. All of these can usually be controlled with other medications. Temodar® is either given at a low dose every day while you are undergoing radiation or at a higher dose for 5 days out of every month.
Some of the other chemotherapy regimens used for brain tumors include carmustine (BCNU), lomustine (CCNU) and a combination of three drugs called PCV (procarbazine, CCNU and vincristine).
What kinds of tumors respond to chemotherapy?
Anaplastic astroctyoma and Glioblastoma Multiforme are known to have some response to Temodar. Anaplastic Oligodendrogliomas and Primary Central Nervous System Lymphoma are two other tumor types that are especially sensitive to chemotherapy.
What are targeted therapies?
These are drugs that have been specifically developed to target a mechanism or pathway that is active in a type of tumor. None of these therapies have been proven to be effective against brain tumors yet, but are currently being studied and may be an option in a clinical trial.
Types of Blood Cells
- White blood cells (fight infection)
- Red blood cells (deliver oxygen)
- Platelets (necessary for clotting)