Systemic Radiation Therapy
Certain cancers may be treated by swallowing radioactive pills or receiving radioactive fluids in the vein (intravenous). This type of treatment is called systemic radiation therapy because the medicine goes to the entire body. For example, radioactive iodine (I-131) capsules are given to treat some types of thyroid cancer. Another example is the use of intravenous radioactive material to treat pain due to cancer that has spread to the bone. Radiolabeled antibodies are monoclonal antibodies with radioactive particles attached. These antibodies are designed to attach themselves directly to the cancer cell and damage it with small amounts of radiation.
Novel Targeted Therapies
Cancer doctors now know much more about how cancer cells function. New cancer therapies use this information to target cancer cell functions and stop them. Called targeted therapies, they can be more specific in stopping cancer cells from growing and may make other treatments work better. For example, some medicines work to prevent cancers from growing by preventing the growth of new blood vessels that would nourish the cancer.
Other targeted therapies work more directly on cancer cells by blocking the action of molecules on the surface of cancer cells called growth factors.
Any drug that can make tumor cells more sensitive to radiation is called a radiosensitizer. Combining radiation with radiosensitizers may allow doctors to kill more tumor cells. Some types of chemotherapy and some novel targeted therapies can act as radiosensitizers.
Some medicines called radioprotectors can help protect healthy tissue from the effects of radiation.
Intraoperative Radiation Therapy
Radiation therapy given during surgery is called intraoperative radiation therapy. Intraoperative radiation therapy is helpful when vital normal organs are too close to the tumor. During an operation, a surgeon temporarily moves the normal organs out of the way so radiation can be applied directly to the tumor. This allows your radiation oncologist to avoid exposing those organs to radiation. Intraoperative radiation can be given as external beam therapy or as brachytherapy.
Medicines prescribed by a medical oncologist that can kill cancer cells directly are called chemotherapy. Some are given in pill form, and some are given by injection. Chemotherapy can also be considered a type of systemic therapy, because medicines go through the bloodstream to the entire body.
Some treatments are designed to help your own body’s immune system fight the cancer, similar to how your body fights off infections.