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.

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.

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

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.

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.

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.

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.

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.

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.

Also called radioisotope. 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.

Also called radioactive drug. 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 (the spreading of breast cancer to the bones).

A medicine that makes tumor cells more sensitive to radiation therapy.

Also called irradiation and radiation therapy. 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 radiotherapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body.

Also called Evista. A medicine used to reduce the risk of invasive breast cancer in postmenopausal women who are at high risk of the disease or who have osteoporosis. It is also used to prevent and treat osteoporosis in postmenopausal women. It is also being studied in the prevention of breast cancer in certain premenopausal women and in the prevention and treatment of other conditions. Raloxifene hydrochloride blocks the effects of the hormone estrogen in the breast and increases the amount of calcium in bone. It is a type of selective estrogen receptor modulator (SERM).

A study in which the participants are assigned by chance to separate groups that compare different treatments; neither the researchers nor the participants can choose which group. Using chance to assign to groups means that the groups will be similar, and that the treatments they receive can be compared objectively. At the time of the trial, it is not known which treatment is best. It is the participant's choice to be in a randomized trial.

Also called Response Evaluation Criteria In Solid Tumors. A standard way to measure how well a person with cancer responds to treatment. It is based on whether tumors shrink, stay the same, or get bigger. To use RECIST, there must be at least one tumor that can be measured on X-rays, CT scans or MRI scans. The types of response a person can have are a complete response (CR), a partial response (PR), progressive disease (PD), and stable disease (SD).

Surgery that is done to reshape or rebuild (reconstruct) a part of the body changed by previous surgery. There are several types of reconstructive surgeries available after breast cancer treatment surgeries.

Also called recurrent cancer. Breast cancer that has returned after a period of time. The cancer may come back to the same place as the original (primary) breast tumor or to another place in the body.

In medicine, the act of a doctor sending a person he or she is caring for to another doctor for additional healthcare services. For instance, an oncologist may refer to other specialists during breast cancer treatment. Specialists who work in breast cancer treatment include medical oncologists, radiologists, breast surgeons, surgical oncologists, and radiation oncologists.

In medicine, describes a disease or condition that does not respond to treatment.

A treatment plan that specifies the dosage, the schedule and the duration of treatment.

A temporary loss of feeling or awareness in a part of the body, such as an arm or a leg, caused by special medicines or other substances called anesthetics. The individual receiving treatment stays awake, but has no feeling in the part of the body treated with the anesthetic.

Treatment with anticancer medicines directed to a specific area of the breast.

A surgical procedure to remove some of the lymph nodes that drain lymph from the area around a breast tumor. The lymph nodes are then examined under a microscope to see if breast cancer cells have spread to them.

A decrease in the size of a breast tumor or in the extent of cancer in the body.

A healthcare professional who helps people recover from an illness or injury and return to daily life. Examples of rehabilitation specialists are physical therapists and occupational therapists.

A specific measurement of survival. For breast cancer, the rate is calculated by adjusting the survival rate to remove all causes of death except breast cancer. The rate is determined at specific time intervals, such as 2 years and 5 years after diagnosis.

A decrease in or disappearance of signs and symptoms of breast cancer. In partial remission, some, but not all, signs and symptoms of cancer have disappeared. In complete remission, all signs and symptoms of cancer have disappeared, although breast cancer still may be in the body.

A type of internal radiation treatment in which the radioactive source is removed between treatments. Also called high-dose-rate remote brachytherapy and high-dose-rate remote radiation therapy.

A scientific study of nature that sometimes includes processes involved in health and disease. For example, clinical trials are research studies that involve people. These studies may be related to new ways to screen, prevent, diagnose and treat disease. They may also study certain outcomes and certain groups of people by looking at data collected in the past or future.

Removed by surgery.

Breast cancer cells that remain after attempts to remove the cancer have been made.

A process in which a substance, such as tissue, is lost by being destroyed and then absorbed by the body.

The percent of people whose breast cancer shrinks or disappears after treatment.

Also called case-control study. A study that compares two groups of people: those with the disease or condition under study (cases) and a very similar group of people who do not have the disease or condition (controls). Researchers study the medical and lifestyle histories of the people in each group to learn what factors may be associated with the disease or condition. For example, one group may have been exposed to a particular substance that the other was not.