Chemotherapy uses drugs to kill cancer cells.
Chemotherapy may be taken by pill, or it may be put into the body by a needle in the vein or muscle. Chemotherapy is called a systemic treatment because the drug enters the bloodstream, travels through the body, and can kill cancer cells outside the lungs. Chemoprevention uses drugs to prevent a second cancer from occurring. One new type of radiation therapy is called radiosurgery. In radiosurgery, radiation is directly focused on the tumor, and involves as little normal tissue as possible.