Surgery involves the removal of the tumor and some of the surrounding normal tissues. This is a very localized form of treatment. Radiation therapy involves the use of high-energy rays to destroy cancer cells.
Radiation therapy is also a localized form of treatment.
However, it is broader in scope than surgery because organs that cannot be removed surgically can usually be treated with irradiation. Chemotherapy uses anticancer medication to destroy cancer cells. The drugs may be given by mouth, intramuscularly, or intravenously. Because the chemotherapy travels throughout the body, it can eradicate cancer cells in remote locations. Many cancers are treated with a combination of these treatment modalities .