Chemotherapy is the use of medicines or drugs to treat disease. Many times this treatment is called just "chemo." Surgery and radiation therapy remove, kill, or damage cancer cells in a certain area, but chemo works throughout the whole body. Chemo can kill cancer cells that have metastasized or spread to parts of the body far away from the primary (original) tumor.

More than 100 chemo drugs are used in many combinations. A single chemo drug can be used to treat cancer. But for the most part, the drugs work better when used in certain combinations. Your chemo treatment will likely include more than one drug. This is called combination chemotherapy. A combination of drugs with different actions can work together to kill more cancer cells. It can also reduce the chance that the cancer may become resistant to any one chemo drug.

You and your doctor will decide what drug or combination of drugs you will get. Your doctor will choose the doses, how the drugs will be given, and how often and how long you will get treatment. All of these decisions will depend on the type of cancer, where it is, how big it is, and how it is affecting your normal body functions and overall health.

Last Medical Review: 08/28/2008
Last Revised: 09/11/2008