All but surgery can be performed on an outpatient basis. The physician may use one form of therapy or a number of different forms in order to produce the desired results. Its effectiveness as a treatment for cancer was first reported in the late 1800s. Advances in equipment technology, combined with the science of radiobiology, have led to today's highly sophisticated treatment centers. Radiation therapy can now be delivered with maximum therapeutic benefits, minimizing toxicity and sparing healthy tissues.
Radiation therapy uses high-energy ionizing radiation to kill cancer cells.
It is considered a local therapy because the cancer cells are destroyed only in the anatomical area being treated. The radiation causes a breakage of one or both stands of the DNA molecule inside the cells, therefor preventing their ability to grow and divide. While cells in all phases of the cell cycle can be damaged by radiation, the lethal effect of radiation may not be apparent until after one or more cell divisions have occurred. Although normal cells can also be affected by ionizing radiation, they are usually better able to repair their DNA damage. Radiation treatments can be administered externally or internally, depending on the type and extent of the tumor, however only external radiation can be administered in an out-patient basis.