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Glossary - R


Showing 1-35 out of 35 Terms

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  • Radiation


    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). Radiation can damage cells. It is used to diagnose and treat some types of cancer.

  • Radiation Enteritis

    (RAY-dee-AY-shun EN-teh-RY-tis)

    Inflammation of the small intestine caused by radiation therapy to the abdomen, pelvis, or rectum. Symptoms include nausea, vomiting, abdominal pain and cramping, frequent bowel movements, watery or bloody diarrhea, fatty stools, and weight loss. Some of these symptoms may continue for a long time.

  • Radiation oncologist

    (RAY-dee-AY-shun on-KAH-loh-jist)

    A doctor who specializes in using radiation to treat cancer.

  • Radiation recall

    Inflammation of exposed skin and underlying organs in sites of previous radiation therapy.

  • Radiation therapy

    RAY-dee-AY-shun THAYR-uh-pee

    Treatment with high-energy x-rays to kill cancer cells or shrink tumors. The radiation may come from outside of the body (external radiation) or from radioactive materials placed directly in the tumor (internal or implant radiation). Radiation therapy may be used to reduce the size of a cancer before surgery, to destroy any remaining cancer cells after surgery, or, in some cases, may be the main treatment.

  • Radioactive


    Giving off radiation.

  • Radiologist


    A doctor who has special training in creating and interpreting pictures of areas inside the body. The pictures are made with x-rays, sound waves, or other types of energy.

  • Radiosurgery


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

  • Rectal


    By or having to do with the rectum. The rectum is the last several inches of the large intestine closest to the anus.

  • Rectally


    By or having to do with the rectum. The rectum is the last several inches of the large intestine closest to the anus.

  • Rectum


    The last part of your large intestine.

  • Recurrent


    Cancer that has recurred (come back), usually after a period of time during which the cancer could not be detected. The cancer may come back to the same place as the original (primary) tumor or to another place in the body. Also called recurrence.

  • Red blood cells

    Blood cells that carry oxygen to the cells throughout your body.

  • Refractory


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

  • Regimen


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

  • Regional


    In oncology, describes the body area right around a tumor.

  • Regional chemotherapy

    (REE-juh-nul KEE-moh-THAYR-uh-pee)

    Treatment with anticancer drugs directed to a specific area of the body.

  • Regression


    The reduction of cancer, usually as the result of therapy; it is shown by decreased size of the tumor or tumors.

  • Rehabilitation


    In medicine, a process to restore mental and/or physical abilities lost to injury or disease, in order to function in a normal or near-normal way.

  • Reinduction

    To start over, i.e. A new treatment or protocol.

  • Relapse


    Reappearance of cancer after a disease-free period.

  • Remission

    Complete or partial disappearance of the signs and symptoms of cancer in response to treatment; the period during which a disease is under control. A remission may not be a cure.

  • Renal

    Pertaining to your kidneys.

  • Reproductive hormones

    (REE-proh-DUK-tiv HOR-mone)

    A type of hormone involved in fertility and sexuality. Reproductive hormones are usually made in the ovaries (in females) and testes (in males). Female reproductive hormones include estrogen and progesterone. They help develop and maintain female sex characteristics and play an important role in the menstrual cycle, fertility, and pregnancy. Male reproductive hormones, such as testosterone, help develop and maintain male sex characteristics and help make sperm in the testes. Some reproductive hormones may also be made in the laboratory and used to treat certain medical conditions.

  • Research

    A scientific way to examine a problem, answer a question or gain new information.

  • Resection


    Surgery to remove tissue or part or all of an organ.

  • Resident

    A physician in the second or third year of training after completing medical school.

  • Resistance

    The inherent ability of an organism to resist harmful influences.

  • Respiration

    The process of breathing.

  • Respiratory tract

    (RES-pih-ruh-TOR-ee trakt)

    All parts of your body used for breathing.

  • Retina


    The light-sensitive layers of nerve tissue at the back of the eye that receive images and sends them as electric signals through the optic nerve to the brain.

  • Retinoblastoma


    Cancer that forms in the tissues of the retina (the light-sensitive layers of nerve tissue at the back of the eye). Retinoblastoma usually occurs in children younger than 5 years. It may be hereditary or nonhereditary (sporadic).

  • Rhabdomyosarcoma


    Cancer that forms in the soft tissues in a type of muscle called striated muscle. Rhabdomyosarcoma can occur anywhere in the body.

  • Risk group

    (risk groop)

    In medicine, risk groups are used to describe people who are alike in important ways. For example, patients with the same type of cancer may be divided into different risk groups that depend on certain aspects of their disease. These risk groups may be based on the patients chance of being cured (good versus poor) or the chance that their disease will come back (high versus low). Treatment may be based on which risk group a patient falls into. Risk groups can also be used to describe people who share traits and behaviors that affect their chance of developing a disease. For example, people who do not smoke are in a lower risk group for lung cancer than people who smoke.

  • Rituximab


    A drug used alone or with other drugs to treat certain types of B-cell non-Hodgkin lymphoma that are CD20 positive. It is used under the brand names Truxima and Rituxan to treat these cancers. Rituximab is also used under the brand name Rituxan to treat chronic lymphocytic leukemia that is CD20 positive. It is also being studied in the treatment of other conditions and types of cancer. Rituximab binds to a protein called CD20, which is found on B cells and some types of cancer cells. This may help the immune system kill cancer cells. Rituximab is a type of monoclonal antibody.