Radiation therapy, which is used with more than half of all cancer patients, can effectively treat many kinds of cancer in almost any part of the body.  This type of therapy uses x-rays several times stronger than those used for common diagnostic purposes. It is a localized treatment that is applied just to the area affected by the tumor. It is used to:

• shrink a tumor before surgery
• stop the growth of any cancer cells that remain after surgery
• destroy the cancer, usually with chemotherapy and instead of surgery
• improve the quality of life, by shrinking tumors and reducing pressure, bleeding and pain

All cells, both normal and malignant, must reproduce in order to survive. In order to reproduce, the cells must have healthy genetic material called DNA. Radiation given to patients damages the DNA in cancer cells. When cancer cells try to reproduce with their damaged DNA, they die. Because it takes time for the cancer cells to die, patients must continue to be observed even after treatments are completed.

Radiation therapy is usually conducted on an outpatient basis, spanning several days or weeks.

Side Effects

With radiation therapy, the side effects depend on the treatment dose and the part of the body that is treated. The most common side effects are tiredness, skin reactions (such as a rash or redness) in the treated areas and loss of appetite. Radiation therapy may also cause a decrease in the number of white blood cells that help protect the body against infection. Although the side effects of radiation therapy can be unpleasant, the doctor can usually treat or control them. In most cases, these side effects are temporary.