Words to Know

radiation brachytherapy

A type of radiation therapy in which radioactive material - sealed in needles, seeds, wires, or catheters - is placed directly into or near a tumor. Also called brachytherapy, implant radiation therapy, internal radiation therapy.

radiation dermatitis

A skin condition that is a common side effect of radiation therapy. The affected skin becomes painful, red, itchy and blistered. A method to prevent radiation dermatitis is being studied.

radiation fibrosis

The formation of scar tissue as a result of radiation therapy for the treatment of breast cancer.

radiation necrosis

The death of healthy tissue caused by radiation therapy. Radiation necrosis is a side effect of radiation therapy given to kill cancer cells, and can occur after cancer treatment has ended.

radiation nurse

A health professional who specializes in caring for people who are receiving radiation therapy for the treatment of breast cancer.

radiation oncologist

A doctor who specializes in using radiation therapy for the treatment of breast cancer.

radiation physicist

A person who makes sure that the radiation machine delivers the right amount of radiation to the correct site in the body. The physicist works with the radiation oncologist to choose the treatment schedule and dose that has the best chance of killing the most breast cancer cells.

radiation surgery

A type of external radiation therapy that uses special equipment to position the individual in treatment, and precisely give a single large dose of radiation to the tumor. It is used to treat brain tumors caused by metastasis and other brain disorders that cannot be treated by regular surgery. Also called radiosurgery, stereotactic radiosurgery, stereotaxic radiosurgery.

radiation therapist

A healthcare professional who gives radiation treatment.

radiation therapy

Also called irradiation and radiotherapy. The use of high-energy radiation from X-rays, gamma rays, neutrons, protons, and other sources to kill breast cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body.


Energy released in the form of particle or electromagnetic waves. Common sources of radiation include radon gas, cosmic rays from outer space, medical X-rays, and energy given off by a radioisotope (unstable form of a chemical element that releases radiation as it breaks down and becomes more stable).

radical lymph node dissection

A surgical procedure to remove most or all of the lymph nodes located in the underarm area (axillary area) that drain lymph from the area around a breast tumor. The lymph nodes are then examined under a microscope by a pathologist to see if breast cancer cells have spread to them.

radical mastectomy

Also called Halsted radical mastectomy. Surgery for breast cancer in which the breast, chest muscles, and all of the lymph nodes under the arm are removed. For many years, this was the breast cancer operation used most often, but it is used rarely now. Doctors consider radical mastectomy only when the tumor has spread to the chest muscles.

radioactive drug

Also called radiopharmaceutical. A medicine that contains a radioactive substance and is used in the diagnosis and treatment of breast cancer. It can also be used for pain management of bone cancer metastases.

radioactive seed

A small, radioactive pellet that is placed in or near a breast tumor. Cancer cells are killed by the energy given off as the radioactive material breaks down and becomes more stable.


Giving off radiation.


Also called radionuclide. An unstable form of a chemical element that releases radiation as it breaks down and becomes more stable. Radioisotopes can be used in imaging tests or as a treatment for breast cancer.

radiologic exam

A test that uses radiation or other imaging procedures to find signs of breast cancer or other abnormalities in the body: for example, chest X-ray or mammogram.


A doctor who specializes in creating and interpreting pictures of areas inside the body. The pictures are produced with X-rays, sound waves, or other types of energy.


The use of radiation (such as X-rays) or other imaging technologies (such as ultrasound and magnetic resonance imaging) to diagnose or treat disease.