National Cancer Institute
U.S. National Institutes of Health | www.cancer.gov

NCI Home
Cancer Topics
Clinical Trials
Cancer Statistics
Research & Funding
News
About NCI
Dictionary of Cancer Terms
In English   En español
Page Options
Print This Page
Quick Links
Director's Corner
Updates from the Director

Dictionary of Cancer Terms
Cancer-related terms

NCI Drug Dictionary
Definitions, names, and links

Funding Opportunities
Research and training

NCI Publications
Order/download free booklets

Advisory Boards and Groups
Information, meetings, reports

Science Serving People
Learn more about NCI

Español
Información en español
NCI Highlights
NCI Responds to Hurricanes

The Cancer Genome Atlas Reports Brain Tumors Study

The Nation's Investment in Cancer Research FY 2009

Cancer Trends Progress Report: 2007 Update

Past Highlights
You CAN Quit Smoking Now!
Search for
# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

228 results found for:   
  R



R-flurbiprofen  
A substance that is being studied as a treatment for cancer. It belongs to the family of drugs called nonsteroidal anti-inflammatory drugs (NSAIDs).

r-tPA  
A form of tissue plasminogen activator that is made in the laboratory. It helps dissolve blood clots and is used to treat heart attacks, strokes, and clots in the lungs. It is also being studied in the treatment of cancer. It is a type of systemic thrombolytic agent. Also called recombinant tissue plasminogen activator, Activase, and Alteplase.

R101933  
A substance that is being studied for its ability to make cancer cells respond to drugs to which they have become resistant. It belongs to the family of drugs called multidrug resistance inhibitors.

R115777  
A substance that is being studied in the treatment of acute myeloid leukemia (AML) and other types of cancer. It belongs to the family of drugs called farnesyltransferase inhibitors. Also called tipifarnib and Zarnestra.

R1507  
A human monoclonal antibody being studied in the treatment of several types of cancer. Monoclonal antibodies are made in the laboratory and can locate and bind to substances in the body, including cancer cells. R1507 blocks the action of a protein needed for cell growth and may kill cancer cells. It is a type of insulin-like growth factor-1 receptor (IGF-1R) inhibitor.

rabies  
A disease of the nervous system caused by the rabies virus. Rabies is marked by an increase in saliva production, abnormal behavior, and eventual paralysis and death.

rAd/p53  
A substance that has been studied in the treatment of some types of cancer. rAd/p53 is a weakened adenovirus that carries the p53 gene into tumor cells, causing them to die. It is a type of gene therapy. Also called recombinant adenovirus-p53, ACN53, and SCH-58500.

radiation  (RAY-dee-AY-shun)
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 brachytherapy  (RAY-dee-AY-shun BRAY-kee-THAYR-uh-pee)
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, internal radiation therapy, and implant radiation therapy.

radiation dermatitis  (RAY-dee-AY-shun DER-muh-TY-tis)
A skin condition that is a common side effect of radiation therapy. The affected skin becomes painful, red, itchy, and blistered.

radiation enteritis  (RAY-dee-AY-shun EN-tuh-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 fibrosis  (RAY-dee-AY-shun fy-BROH-sis)
The formation of scar tissue as a result of radiation therapy.

radiation necrosis  (RAY-dee-AY-shun neh-KROH-sis)
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.

radiation oncologist  (RAY-dee-AY-shun on-KAH-loh-jist)
A doctor who specializes in using radiation to treat 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 cancer cells.

radiation surgery  (RAY-dee-AY-shun SER-juh-ree)
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 stereotaxic radiosurgery, stereotactic radiosurgery, and radiosurgery.

radiation therapist  
A health professional who gives radiation treatment.

radiation therapy  (RAY-dee-AY-shun THAYR-uh-pee)
The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill 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 radiotherapy and irradiation.

radical cystectomy  (RA-dih-kul sis-TEK-toh-mee)
Surgery to remove all of the bladder (the organ that holds urine) as well as nearby tissues and organs.

radical hysterectomy  (RA-dih-kul HIS-teh-REK-toh-mee)
Surgery to remove the uterus, cervix, and part of the vagina. The ovaries, fallopian tubes, and nearby lymph nodes may also be removed.

radical local excision  (RA-dih-kul LOH-kul ek-SIH-zhun)
Surgery to remove a tumor and a large amount of normal tissue surrounding it. Nearby lymph nodes may also be removed.

radical lymph node dissection  
A surgical procedure to remove most or all of the lymph nodes that drain lymph from the area around a tumor. The lymph nodes are then examined under a microscope to see if cancer cells have spread to them.

radical mastectomy  (RA-dih-kul ma-STEK-toh-mee)
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 Halsted radical mastectomy.

radical nephrectomy  (RA-dih-kul neh-FREK-toh-mee)
Surgery to remove an entire kidney, nearby adrenal gland and lymph nodes, and other surrounding tissue.

radical perineal prostatectomy  (RA-dih-kul PAYR-ih-NEE-ul PROS-tuh-TEK-toh-mee)
Surgery to remove all of the prostate through an incision between the scrotum and the anus. Nearby lymph nodes are sometimes removed through a separate incision in the wall of the abdomen.

radical prostatectomy  (RA-dih-kul PROS-tuh-TEK-toh-mee)
Surgery to remove the entire prostate. The two types of radical prostatectomy are retropubic prostatectomy (surgery through an incision in the wall of the abdomen) and perineal prostatectomy (surgery through an incision between the scrotum and the anus).

radical retropubic prostatectomy  (RA-dih-kul reh-troh-PYOO-bik PROS-tuh-TEK-toh-mee)
Surgery to remove all of the prostate and nearby lymph nodes through an incision in the wall of the abdomen.

radical vulvectomy  (RA-dih-kul vul-VEK-toh-mee)
Surgery to remove the entire vulva (the external female genital organs, including the clitoris, vaginal lips, and the opening to the vagina) and nearby lymph nodes.

radioactive  (RAY-dee-oh-AK-tiv)
Giving off radiation.

radioactive drug  (RAY-dee-oh-AK-tiv...)
A drug containing a radioactive substance that is used in the diagnosis and treatment of cancer and in pain management of bone metastases. Also called a radiopharmaceutical.

radioactive fallout  (RAY-dee-oh-AK-tiv...)
Airborne radioactive particles that fall to the ground during and after an atomic bombing, nuclear weapons test, or nuclear plant accident.

radioactive iodine  (RAY-dee-oh-AK-tiv I-oh-dine)
A radioactive form of iodine, often used for imaging tests or to treat an overactive thyroid, thyroid cancer, and certain other cancers. For imaging tests, the patient takes a small dose of radioactive iodine that collects in thyroid cells and certain kinds of tumors and can be detected by a scanner. To treat thyroid cancer, the patient takes a large dose of radioactive iodine, which kills thyroid cells. Radioactive iodine is also used in internal radiation therapy for prostate cancer, intraocular (eye) melanoma, and carcinoid tumors. Radioactive iodine is given by mouth as a liquid or in capsules, by infusion, or sealed in seeds, which are placed in or near the tumor to kill cancer cells.

radioactive palladium  (RAY-dee-oh-AK-tiv puh-LAY-dee-um)
A radioactive form of palladium (a metallic element that resembles platinum). When used to treat prostate cancer, radioactive seeds (small pellets that contain radioactive palladium) are placed in the prostate. Cancer cells are killed by the energy given off as the radioactive material breaks down and becomes more stable.

radioactive seed  (RAY-dee-oh-AK-tiv...)
A small, radioactive pellet that is placed in or near a tumor. Cancer cells are killed by the energy given off as the radioactive material breaks down and becomes more stable.

radiofrequency ablation  (RAY-dee-oh-FREE-kwen-see uh-BLAY-shun)
A procedure that uses radio waves to heat and destroy abnormal cells. The radio waves travel through electrodes (small devices that carry electricity). Radiofrequency ablation may be used to treat cancer and other conditions.

radioimaging  (RAY-dee-oh-IH-muh-jing)
A method that uses radioactive substances to make pictures of areas inside the body. The radioactive substance is injected into the body, and locates and binds to specific cells or tissues, including cancer cells. Images are made using a special machine that detects the radioactive substance.

radioimmunodiagnostics  (RAY-dee-oh-IH-myoo-noh-DY-ug-NOS-tix)
The use of radiolabeled monoclonal antibodies to help diagnose diseases, including cancer. The radiolabeled monoclonal antibody locates and binds to substances in the body, including cancer cells. Images are made using a special machine that detects the radioactive monoclonal antibody.

radioimmunoguided surgery  (RAY-dee-oh-IH-myoo-noh-GIDE-ed SER-juh-ree)
A procedure that uses radioactive substances to locate tumors so that they can be removed by surgery.

radioimmunotherapeutics  (RAY-dee-oh-IH-myoo-noh-THAYR-uh-PYOO-tix)
The use of radiolabeled monoclonal antibodies to treat diseases, including cancer. The radiolabeled monoclonal antibody locates and binds to substances in the body, including cancer cells. Radiation given off by the radioisotope may help kill the cancer cells.

radioimmunotherapy  (RAY-dee-oh-IH-myoo-noh-THAYR-uh-pee)
A type of systemic radiation therapy in which a radioactive substance is linked to an antibody that locates and kills tumor cells when injected into the body.

radioisotope  (RAY-dee-oh-I-suh-tope)
An unstable form of a chemical element that releases radiation as it breaks down and becomes more stable. Radioisotopes may occur in nature or be made in a laboratory. In medicine, they are used in imaging tests and in treatment. Also called radionuclide.

radiolabeled  (RAY-dee-oh-LAY-buld)
Any compound that has been joined with a radioactive substance.

radiologic exam  (RAY-dee-uh-LAH-jik ig-ZAM)
A test that uses radiation or other imaging procedures to find signs of cancer or other abnormalities.

radiologist  (RAY-dee-AH-loh-jist)
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.

radiology  (RAY-dee-AH-loh-jee)
The use of radiation (such as x-rays) or other imaging technologies (such as ultrasound and magnetic resonance imaging) to diagnose or treat disease.

radionuclide  (RAY-dee-oh-NOO-klide)
An unstable form of a chemical element that releases radiation as it breaks down and becomes more stable. Radionuclides may occur in nature or be made in a laboratory. In medicine, they are used in imaging tests and in treatment. Also called radioisotope.

radionuclide scanning  (RAY-dee-oh-NOO-klide SKAN-ing)
A procedure that produces pictures (scans) of structures inside the body, including areas where there are cancer cells. Radionuclide scanning is used to diagnose, stage, and monitor disease. A small amount of a radioactive chemical (radionuclide) is injected into a vein or swallowed. Different radionuclides travel through the blood to different organs. A machine with a special camera moves over the person lying on a table and detects the type of radiation given off by the radionuclides. A computer forms an image of the areas where the radionuclide builds up. These areas may contain cancer cells. Also called scintigraphy.

radiopharmaceutical  (RAY-dee-oh-FAR-muh-SOO-tih-kul)
A drug containing a radioactive substance that is used in the diagnosis and treatment of cancer and in pain management of bone metastases. Also called a radioactive drug.

radiosensitization  (RAY-dee-oh-SEN-sih-tih-ZAY-shun)
The use of a drug that makes tumor cells more sensitive to radiation therapy.

radiosensitizer  (RAY-dee-oh-SEN-sih-TIZE-er)
A drug that makes tumor cells more sensitive to radiation therapy.

radiosurgery  (RAY-dee-oh-SER-juh-ree)
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 stereotaxic radiosurgery, stereotactic radiosurgery, and radiation surgery.

radiotherapy  (RAY-dee-oh-THAYR-uh-pee)
The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill 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 radiation therapy and irradiation.

radon  (RAY-don)
A radioactive gas that is released by uranium, a substance found in soil and rock. Breathing in too much radon can damage lung cells and may lead to lung cancer.

Raftilose Synergy 1  (RAF-tih-lose SIH-ner-gee 1)
A substance that is used to improve the health of the digestive system and bones and is being studied in the prevention of colon cancer. Raftilose Synergy 1 is made by combining two starches, oligofructose and inulin. These substances occur naturally in many plants, including chicory root, wheat, bananas, onion, and garlic. Raftilose Synergy 1 helps healthy bacteria grow in the intestines and helps the body absorb calcium and magnesium. Also called oligofructose-enriched inulin.

raloxifene  (ral-OX-ih-feen)
A drug used to reduce the risk of invasive breast cancer in postmenopausal women who are at a high risk of developing the disease or who have osteoporosis. It is also used to prevent and treat osteoporosis in postmenopausal women and is being studied in the prevention and treatment of other conditions. Raloxifene 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). Also called raloxifene hydrochloride and Evista.

raloxifene hydrochloride  (ral-OX-ih-feen HY-droh-KLOR-ide)
A drug used to reduce the risk of invasive breast cancer in postmenopausal women who are at a high risk of developing the disease or who have osteoporosis. It is also used to prevent and treat osteoporosis in postmenopausal women and is being studied 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). Also called raloxifene and Evista.

raltitrexed  
An anticancer drug that stops tumor cells from growing by blocking the ability of cells to make DNA. It belongs to the family of drugs called thymidylate synthase inhibitors. Also called ICI D1694.

randomization  
When referring to an experiment or clinical trial, the process by which animal or human subjects are assigned by chance to separate groups that compare different treatments or other interventions. Randomization gives each participant an equal chance of being assigned to any of the groups.

randomized clinical trial  
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 people 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 patient's choice to be in a randomized trial.

ranpirnase  
A substance being studied in the treatment of cancer. It is a type of ribonuclease enzyme. Also called Onconase.

Rapamune  (RAP-uh-MYOON)
A drug used to prevent the rejection of organ and bone marrow transplants by the body. Rapamune is an antibiotic that blocks a protein involved in cell division and inhibits the growth and function of certain T cells of the immune system that are involved in the body's rejection of foreign tissues and organs. It is a type of immunosuppressant and a type of serine/threonine kinase inhibitor. Rapamune was previously called rapamycin. Also called sirolimus.

rapamycin  (RAP-uh-MY-sin)
A drug used to prevent the rejection of organ and bone marrow transplants by the body. Rapamycin is an antibiotic that blocks a protein involved in cell division and inhibits the growth and function of certain T cells of the immune system involved in the body's rejection of foreign tissues and organs. It is a type of immunosuppressant and a type of serine/threonine kinase inhibitor. Rapamycin is now called sirolimus.

rapid eye movement sleep  
One of the five stages of sleep. During rapid eye movement sleep, the eyes move rapidly while closed and dreams occur. Rapid eye movement sleep is the lightest stage of sleep, during which a person may wake easily. During several hours of normal sleep, a person will go through several sleep cycles that include rapid eye movement sleep and the 4 stages of non-rapid eye movement (light to deep sleep). Also called REM sleep.

rapid hormone cycling  
A procedure in which drugs that block the production of male hormones are alternated with male hormones and/or drugs that promote the production of male hormones. This procedure is being studied in the treatment of prostate cancer.

rapid-onset opioid  
An opioid that relieves pain quickly. Opioids are drugs similar to opiates such as morphine and codeine but do not contain and are not made from opium.

Raptiva  (rap-TEE-vuh)
A monoclonal antibody used to treat psoriasis (a chronic skin disease). It is also being studied in the treatment of graft-versus-host disease (GVHD) of the skin after a donor stem cell transplant. Raptiva binds to a molecule called LFA-1, and blocks the action of T cells (a type of white blood cell). It is a type of immunosuppressant. Also called efalizumab.

ras gene  
A gene that has been found to cause cancer when it is altered (mutated). Agents that block its activity may stop the growth of cancer.

ras peptide  (rass PEP-tide)
A short piece of the ras protein, which is made by the ras gene. The ras gene has been found to cause cancer when it is mutated (changed).

rasburicase  
A drug that is used to treat high blood levels of uric acid in patients receiving treatment for cancer.

rattlesnake root  
An eastern North American perennial herb. A substance obtained from the root of the plant has been used in some cultures to treat a number of medical problems. It is being studied in the treatment of hot flashes and other symptoms of menopause. The scientific name is Cimicifuga racemosa. Also called black cohosh, black snakeroot, bugwort, and bugbane.

rauschpfeffer  (ROWSH-FEH-fer)
An herb native to islands in the South Pacific. Substances taken from the root have been used in some cultures to relieve stress, anxiety, tension, sleeplessness, and problems of menopause. Rauschpfeffer may increase the effect of alcohol and of certain drugs used to treat anxiety and depression. The U.S. Food and Drug Administration advises users that rauschpfeffer may cause severe liver damage. The scientific name is Piper methysticum. Also called kava kava, intoxicating pepper, tonga, and yangona.

RAV12  
A monoclonal antibody that is being studied in the treatment of some types of cancer. Monoclonal antibodies are made in the laboratory and can locate and bind to cancer cells. It binds to a carbohydrate (sugar) molecule that is found on gastric, colon, pancreatic, prostate, ovarian, breast, and kidney cancer cells.

ravuconazole  
A substance that is being studied in the treatment of infections caused by fungi. It belongs to the family of drugs called antifungal agents.

RBC  
Red blood cell. A cell that carries oxygen to all parts of the body. Also called red blood cell and erythrocyte.

rebeccamycin  
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called antineoplastic antibiotics.

rebeccamycin analog  (reh-BEH-kuh-MY-sin A-nuh-log)
A substance that is being studied in the treatment of cancer. It belongs to the families of drugs called antitumor antibiotics and topoisomerase inhibitors. Also called NSC 655649.

Recentin  (reh-SEN-tin)
A substance being studied in the treatment of some types of cancer. Recentin blocks the growth of new blood vessels needed for tumors to grow and may kill cancer cells. It is a type of angiogenesis inhibitor and a type of vascular endothelial growth factor (VEGF) receptor tyrosine kinase inhibitor. Also called AZD2171 and cediranib.

receptor  (reh-SEP-ter)
A molecule inside or on the surface of a cell that binds to a specific substance and causes a specific physiologic effect in the cell.

recombinant  (ree-KOM-bih-nunt)
In genetics, describes DNA, proteins, cells, or organisms that are made by combining genetic material from two different sources. Recombinant substances are made in the laboratory and are being studied in the treatment of cancer and for many other uses.

recombinant adenovirus-p53  (ree-KOM-bih-nunt A-den-oh-VY-rus ...)
A substance that has been studied in the treatment of some types of cancer. Recombinant adenovirus-p53 is a weakened adenovirus that carries the p53 gene into tumor cells, causing them to die. It is a type of gene therapy. Also called SCH-58500, ACN53, and rAd/p53.

recombinant fowlpox-CEA-MUC-1-TRICOM vaccine  (ree-KOM-bih-nunt … vak-SEEN)
A cancer vaccine made with a form of a chicken virus that does not cause disease in humans. It is being studied in the treatment of some types of cancer. The virus is changed in the laboratory to make human proteins that may help immune cells in the body kill tumor cells. Also called falimarev.

recombinant fowlpox-TRICOM vaccine  (ree-KOM-bih-nunt …vak-SEEN)
A cancer vaccine made with a form of a chicken virus that does not cause disease in humans. It is being studied in the treatment of some types of cancer. The virus is changed in the laboratory to make human proteins that may help immune cells in the body kill tumor cells. Also called rF-TRICOM.

recombinant human interleukin-2  (ree-KOM-bih-nunt HYOO-mun in-ter-LOO-kin...)
A drug used to treat some types of cancer. It is an interleukin-2 (a cytokine normally made by immune cells in the body) that is made in the laboratory. Recombinant human interleukin-2 increases the activity and growth of white blood cells called T cells and B cells. It is a type of biological response modifier. Also called aldesleukin and Proleukin.

recombinant tissue plasminogen activator  (ree-KOM-bih-nunt TIH-shoo plaz-MIN-oh-jen AK-tih-vay-tur)
A form of tissue plasminogen activator that is made in the laboratory. It helps dissolve blood clots and is used to treat heart attacks, strokes, and clots in the lungs. It is also being studied in the treatment of cancer. It is a type of systemic thrombolytic agent. Also called r-tPA, Activase, and Alteplase.

recombinant vaccinia-CEA-MUC-1-TRICOM vaccine  (ree-KOM-bih-nunt vak-SIN-ee-uh … vak-SEEN)
A cancer vaccine made with a form of vaccinia virus that does not cause disease in humans. It is being studied in the treatment of some types of cancer. The virus is changed in the laboratory to make human proteins, including the tumor markers called CEA and MUC-1, that may help immune cells in the body kill tumor cells. Also called inalimarev and PANVAC-V.

recombinant vaccinia-TRICOM vaccine  (ree-KOM-bih-nunt vak-SIH-nee-uh … vak-SEEN)
A cancer vaccine made with a form of a vaccinia virus that does not cause disease in humans. It is being studied in the treatment of some types of cancer. The virus is changed in the laboratory to make human proteins that may help immune cells in the body kill tumor cells. Also called vaccinia-TRICOM vaccine and rV-TRICOM.

reconstructive surgeon  
A doctor who can surgically reshape or rebuild (reconstruct) a part of the body, such as a woman's breast after surgery for breast cancer.

reconstructive surgery  
Surgery that is done to reshape or rebuild (reconstruct) a part of the body changed by previous surgery.

recover  (ree-KUH-ver)
To become well and healthy again.

recreational therapy  (...THAYR-uh-pee)
A type of therapy that uses activities to help meet the physical and emotional needs of patients with an illness or disability and help them develop skills for daily living. These activities include arts and crafts, music, spending time with animals, sports, and drama. Recreational therapy is being studied as a way to relieve distress in cancer patients who are being treated for pain.

rectal  
By or having to do with the rectum. The rectum is the last several inches of the large intestine and ends at the anus.

rectal cancer  (REK-tul KAN-ser)
Cancer that forms in the tissues of the rectum (the last several inches of the large intestine before the anus).

rectal reconstruction  (REK-tul REE-kun-STRUK-shun)
Surgery to rebuild the rectum using a section of the colon. This may be done when the rectum has been removed to treat cancer or other diseases.

rectitis  (rek-TY-tis)
Inflammation of the mucous membrane that lines the rectum. Also called proctitis.

rectum  
The last several inches of the large intestine. The rectum ends at the anus.

recur  
To come back or to return.

recurrence  (ree-KER-ents)
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 recurrent cancer.

recurrent cancer  (ree-KER-ent KAN-ser)
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 cell  
RBC. A cell that carries oxygen to all parts of the body. Also called RBC and erythrocyte.

red cedar  (...SEE-der)
A type of evergreen tree with hard fragrant wood that is a member of the cypress family. The oil from the wood is used in soaps, shampoos, bath salts, perfumes, aromatherapy, and to keep insects away. The scientific name is Juniperus virginiana. Also called cedarwood and Eastern red cedar.

red clover  
Trifolium pratense. A plant with flowers that has been used in some cultures to treat certain medical problems. It is being studied in the relief of menopausal symptoms and may have anticancer effects. Also called purple clover, wild clover, and Trifolium pratense.

red date  
The fruit of the jujube plant. It has been used in some cultures to treat certain medical problems.

red elm  
The inner bark of this plant has been used in some cultures to treat certain medical problems. It may have antioxidant effects. Also called slippery elm, gray elm, Indian elm, sweet elm, Ulmus fulva, and Ulmus rubra.

Reed-Sternberg cell  
A type of cell that appears in people with Hodgkin disease. The number of these cells increases as the disease advances.

reflux  
The backward flow of liquid from the stomach into the esophagus.

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

refractory cancer  
Cancer that does not respond to treatment. The cancer may be resistant at the beginning of treatment or it may become resistant during treatment. Also called resistant cancer.

Regenecare  (reh-JEH-neh-KAYR)
A substance being studied in the treatment of certain types of skin rash and skin pain in cancer patients. The ingredients of Regenecare are collagen, aloe vera, vitamin E, and lidocaine. It may help stop bleeding, form new blood vessels, keep the skin moist, and relieve pain and itching. It is a type of topical anesthetic and a type of wound repair agent.

regeneration  
In biology, regrowth of damaged or destroyed tissue or body part.

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 cancer  
Refers to cancer that has grown beyond the original (primary) tumor to nearby lymph nodes or organs and tissues.

regional chemotherapy  (REE-juh-nul KEE-moh-THAYR-uh-pee)
Treatment with anticancer drugs directed to a specific area of the body.

regional enteritis  (REE-juh-nul EN-teh-RY-tis)
Chronic inflammation of the gastrointestinal tract, most commonly the small intestine and colon. Regional enteritis increases the risk for colorectal cancer and small intestine cancer. Also called Crohn disease.

regional lymph node  
In oncology, a lymph node that drains lymph from the region around a tumor.

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

registered dietitian  (...dy-eh-TIH-shun)
A health professional with special training in the use of diet and nutrition to keep the body healthy. A registered dietitian may help the medical team improve the nutritional health of a patient.

Reglan  (REG-lun)
A drug that increases the motility (movements and contractions) of the stomach and upper intestine. It is used to treat certain stomach problems and nausea and vomiting caused by chemotherapy. It is a type of antiemetic and a type of motility agent. Also called metoclopramide.

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

rehabilitation  (REE-huh-BIH-lih-TAY-shun)
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.

rehabilitation specialist  
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.

relapse  
The return of signs and symptoms of cancer after a period of improvement.

relative survival rate  (REH-luh-tiv ser-VY-vul …)
A way of comparing survival of people who have a specific disease with those who don’t. The percentage of survivors is usually determined at specific times, such as 2 years and 5 years after diagnosis or treatment. The relative survival rate shows whether the disease shortens life.

relaxation technique  
A method used to reduce tension and anxiety, and control pain.

Relistor  (REH-lih-stor)
A drug used to relieve certain side effects caused by treatment with opiods (pain killers similar to morphine), such as constipation (hard, dry stools), itching, and low urine flow. Relistor binds to opioid receptors outside the brain and may block the side effects of opioid drugs without affecting their ability to relieve pain. Relistor is a type of peripheral opioid receptor antagonist. Also called methylnaltrexone bromide.

REM sleep  
One of the five stages of sleep. During REM sleep, the eyes move rapidly while closed and dreams occur. REM sleep is the lightest stage of sleep, during which a person may wake easily. During several hours of normal sleep, a person will go through several sleep cycles that include REM sleep and the 4 stages of non-REM (light to deep sleep). Also called rapid eye movement sleep.

Remeron  
A drug used to treat depression. It belongs to the family of drugs called antidepressant agents. Also called mirtazapine.

remission  
A decrease in or disappearance of signs and symptoms of 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 cancer still may be in the body.

remission induction therapy  
Initial treatment with anticancer drugs to decrease the signs or symptoms of cancer or make them disappear.

remote brachytherapy  (...BRA-kee-THAYR-uh-pee)
A type of internal radiation treatment in which the radioactive source is removed between treatments. Also called high-dose-rate remote brachytherapy or high-dose-rate remote radiation therapy.

renal artery  (REE-nal AR-tuh-ree)
The main blood vessel that supplies blood to a kidney and its nearby adrenal gland and ureter. There is a renal artery for each kidney.

renal capsule  
The fibrous connective tissue that surrounds each kidney.

renal cell cancer  
The most common type of kidney cancer. It begins in the lining of the renal tubules in the kidney. The renal tubules filter the blood and produce urine. Also called hypernephroma.

renal collecting tubule  
The last part of a long, twisting tube that collects urine from the nephrons (cellular structures in the kidney that filter blood and form urine) and moves it into the renal pelvis and ureters. Also called collecting duct.

renal failure  (REE-nul FAYL-yer)
A condition in which the kidneys stop working and are not able to remove waste and extra water from the blood or keep body chemicals in balance. Acute or severe renal failure happens suddenly (for example, after an injury) and may be treated and cured. Chronic renal failure develops over many years, may be caused by conditions like high blood pressure or diabetes, and cannot be cured. Chronic renal failure may lead to total and long-lasting kidney failure, called end-stage renal disease (ESRD). A person in ESRD needs dialysis (the process of cleaning the blood by passing it through a membrane or filter) or a kidney transplant. Also called kidney failure.

renal fascia  (REE-nul FA-shuh)
A fibrous envelope of tissue that surrounds the kidney. Also called Gerota's fascia and Gerota's capsule.

renal function test  (REE-nul FUNK-shun...)
A test in which blood or urine samples are checked for the amounts of certain substances released by the kidneys. A higher- or lower-than-normal amount of a substance can be a sign that the kidneys are not working the way they should. Also called kidney function test.

renal glomerulus  
A tiny, round cluster of blood vessels within the kidneys. It filters the blood to reabsorb useful materials and remove waste as urine.

renal pelvis  
The area at the center of the kidney. Urine collects here and is funneled into the ureter, the tube that connects the kidney to the bladder.

renal tubular acidosis  (REE-nul TOO-byoo-ler A-sih-DOH-sis)
A rare disorder in which structures in the kidney that filter the blood are impaired, producing urine that is more acid than normal.

Renova  
A topical preparation of tretinoin that is used to treat acne. Tretinoin is a form of vitamin A.

replicate  
To make a copy or duplicate of something.

replication cycle  (reh-plih-KAY-shun...)
In biology, refers to the reproduction cycle of viruses. A repliction cycle begins with the infection of a host cell and ends with the release of mature progeny virus particles.

reproductive cell  
An egg or sperm cell. Each mature reproductive cell carries a single set of 23 chromosomes.

reproductive system  (REE-pruh-DUK-tiv SIS-tem)
In women, this system includes the ovaries, the fallopian tubes, the uterus (womb), the cervix, and the vagina (birth canal). The reproductive system in men includes the prostate, the testes, and the penis.

resectable  (ree-SEK-tuh-bul)
Able to be removed by surgery.

resected  
Removed by surgery.

resection  (ree-SEK-shun)
A procedure that uses surgery to remove tissue or part or all of an organ.

resectoscope  (reh-SEK-toh-skope)
A thin, tube-like instrument used to remove tissue from inside the body. A resectoscope has a light and lens for viewing. It also has a tool to remove tissue using an electrical current. It is inserted through the urethra to treat prostate disease in men and through the vagina and cervix to treat abnormal uterine bleeding in women.

residual disease  
Cancer cells that remain after attempts to remove the cancer have been made.

resiquimod  (reh-SIH-kwih-mod)
A substance being studied in the treatment of some types of skin cancer. When put on the skin, resiquimod causes some immune cells to make certain chemicals that may help them kill tumor cells. It is also being studied to find out if adding it to a tumor vaccine improves the antitumor immune response. It is a type of imidazoquinoline and a type of immunomodulator.

resistant cancer  
Cancer that does not respond to treatment. The cancer may be resistant at the beginning of treatment, or it may become resistant during treatment. Also called refractory cancer.

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

respirator  (RES-pih-RAY-ter)
In medicine, a machine used to help a patient breathe. Also called ventilator.

respiratory syncytial virus  (RES-pih-ruh-TOR-ee sin-SIH-shul VY-rus)
RSV. A virus that causes respiratory infections with cold-like symptoms. Also called RSV.

respiratory system  (RES-pih-ruh-TOR-ee SIS-tem)
The organs that are involved in breathing. These include the nose, throat, larynx, trachea, bronchi, and lungs. Also called respiratory tract.

respiratory therapist  (RES-pih-ruh-TOR-ee THAYR-uh-pist)
A health professional trained to evaluate and treat people who have breathing problems or other lung disorders.

respiratory therapy  (RES-pih-ruh-TOR-ee THAYR-uh-pee)
Exercises and treatments that help improve or restore lung function.

respiratory tract  (RES-pih-ruh-TOR-ee trakt)
The organs that are involved in breathing. These include the nose, throat, larynx, trachea, bronchi, and lungs. Also called respiratory system.

response  (reh-SPONTS)
In medicine, an improvement related to treatment.

response rate  (reh-SPONTS...)
The percentage of patients whose cancer shrinks or disappears after treatment.

resting  
In biology, refers to a cell that is not dividing.

resveratrol  (rez-VEER-uh-trol)
A substance found in the skins of grapes and in certain other plants, fruits, and seeds. It is made by various plants to help defend against invading fungi, stress, injury, infection, and too much sunlight. It is being studied in the prevention of cancer and heart disease. It is a type of antioxidant and a type of polyphenol.

retch  (RECH)
The action of the stomach and esophagus to try to vomit (eject some or all of the contents of the stomach). Retching that does not cause vomiting is called dry heaves.

Retin-A  
A topical preparation of tretinoin that is used to treat acne. Tretinoin is a form of vitamin A.

Retin-A-Micro  
A topical preparation of tretinoin that is used to treat acne. Tretinoin is a form of vitamin A.

retina  (RET-ih-nuh)
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  (REH-tih-noh-blas-TOH-muh)
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).

retinoic acid  (REH-tih-NOH-ik A-sid)
A form of vitamin A that is made by the body, and can also be made in the laboratory. It is used to treat acute promyelocytic leukemia, usually together with other drugs, and to treat acne. It is being studied in the treatment and prevention of other types of cancer. Also called all-trans retinoic acid, ATRA, tretinoin, and vitamin A acid.

retinoid  
Vitamin A or a vitamin A-like compound.

retinol  (REH-tih-nol)
An active form of vitamin A found in animal foods such as liver, whole eggs, and whole milk.

retinyl palmitate  
A drug that is being studied in the prevention of cancer. It belongs to the family of drugs called retinoids.

retromolar trigone  (reh-troh-MOH-ler TRY-gone)
The small area behind the wisdom teeth.

retroperitoneal  (REH-troh-PAYR-ih-toh-NEE-ul)
Having to do with the area outside or behind the peritoneum (the tissue that lines the abdominal wall and covers most of the organs in the abdomen).

retropubic prostatectomy  (reh-troh-PYOO-bik PROS-tuh-TEK-toh-mee)
Surgery to remove the prostate through an incision made in the wall of the abdomen.

retrospective  
Looking back at events that have already taken place.

retrospective cohort study  
A research study in which the medical records of groups of individuals who are alike in many ways but differ by a certain characteristic (for example, female nurses who smoke and those who do not smoke) are compared for a particular outcome (such as lung cancer). Also called a historic cohort study.

retrospective 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. Also called a case-control study.

retroviral vector  
RNA from a virus that is used to insert genetic material into cells.

retrovirus  (REH-troh-VY-rus)
A type of virus that has RNA instead of DNA as its genetic material. It uses an enzyme called reverse transcriptase to become part of the host cells’ DNA. This allows many copies of the virus to be made in the host cells. The virus that causes AIDS, the human immunodeficiency virus (HIV), is a type of retrovirus.

ReVia  (reh-VEE-uh)
A drug that blocks the action of opiates (drugs used to treat pain). It may be used in the treatment of intravenous opiate addiction or alcohol dependence. ReVia is also being studied in the treatment of breast cancer. It may block the effects of the hormone estrogen, which causes some breast cancer cells to grow, or block the blood flow to tumors. It is a type of opiate antagonist. Also called naltrexone, naltrexone hydrochloride, and Vivitrol.

Revlimid  (REV-lih-mid)
A drug that is similar to thalidomide, and is used to treat multiple myeloma and certain types of anemia. It is also being studied in the treatment of other types of cancer. Revlimid belongs to the family of drugs called angiogenesis inhibitors. Also called lenalidomide and CC-5013.

RevM10 gene  
An antiviral gene that is being studied in the treatment of cancer in patients who have HIV, the virus that causes AIDS.

Reye syndrome  (RAY SIN-drome)
A rare disease that damages the brain and liver and causes death if not treated. It occurs most often in children younger than 15 years who have had a fever-causing virus, such as chickenpox or flu. Taking aspirin during a viral illness may increase the risk of Reye syndrome.

rF-TRICOM  
A cancer vaccine made with a form of a chicken virus that does not cause disease in humans. It is being studied in the treatment of some types of cancer. The virus is changed in the laboratory to make human proteins that may help immune cells in the body kill tumor cells. Also called recombinant fowlpox-TRICOM vaccine.

RFT5-dgA immunotoxin  (... IH-myoo-noh-TOK-sin)
A monoclonal antibody linked to a toxic substance. It is being studied in the treatment of melanoma that has spread to distant parts of the body. RFT5-dgA immunotoxin is made in the laboratory. It can find and kill certain white blood cells that prevent the immune system from killing cancer cells. Also called IgG-RFT5-dgA.

rhabdoid tumor  
A malignant tumor of either the central nervous system (CNS) or the kidney. Malignant rhabdoid tumors of the CNS often have an abnormality of chromosome 22. These tumors usually occur in children younger than 2 years.

rhabdomyosarcoma  (RAB-doh-MY-oh-sar-KOH-muh)
Cancer that forms in the soft tissues in a type of muscle called striated muscle. Rhabdomyosarcoma can occur anywhere in the body.

rheumatism  
A group of disorders marked by inflammation or pain in the connective tissue structures of the body. These structures include bone, cartilage, and fat.

rheumatoid arthritis  (ROO-muh-TOYD ar-THRY-tis)
An autoimmune disease that causes pain, swelling, and stiffness in the joints, and may cause severe joint damage, loss of function, and disability. The disease may last from months to a lifetime, and symptoms may improve and worsen over time.

Rheumatrex  (ROO-muh-trex)
A drug used to treat some types of cancer, severe skin conditions such as psoriasis, and rheumatoid arthritis. Rheumatrex stops cells from making DNA. It is a type of antimetabolite. Also called methotrexate and amethopterin.

rhinoscope  (RY-noh-skope)
A thin, tube-like instrument used to examine the inside of the nose. A rhinoscope has a light and a lens for viewing and may have a tool to remove tissue. Also called a nasoscope.

rhinoscopy  (ry-NOS-koh-pee)
Examination of the inside of the nose using a rhinoscope. A rhinoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease. Also called nasoscopy.

rhizoxin  
A substance that is being studied in the treatment of cancer. It comes from a fungus and is similar to vinca alkaloid drugs. It belongs to the family of drugs called antimitotic agents.

rhubarb  (ROO-barb)
The root of this plant has been used in some cultures to treat certain medical problems. It may have anti-inflammatory and anticancer effects. The scientific name is Rheum palmatum or Rheum officinale. Also called da-huang, Chinese rhubarb, Indian rhubarb, and Turkish rhubarb.

ribavirin  
A drug used to treat respiratory syncytial virus (RSV) infection in the lungs.

ribonucleic acid  (RY-boh-noo-KLAY-ik A-sid)
RNA. One of the two types of nucleic acids found in all cells. In the cell, ribonucleic acid is made from DNA (the other type of nucleic acid), and proteins are made from ribonucleic acid. Also called RNA.

ribonucleotide reductase inhibitor  
A family of anticancer drugs that interfere with the growth of tumor cells by blocking the formation of deoxyribonucleotides (building blocks of DNA).

Richter syndrome  (RIK-ter SIN-drome)
A rare condition in which chronic lymphocytic leukemia (CLL) changes into a fast-growing type of lymphoma. Symptoms of Richter syndrome include fever, loss of weight and muscle mass, and other health problems. Also called Richter transformation.

Richter transformation  (RIK-ter TRANZ-for-MAY-shun)
A rare condition in which chronic lymphocytic leukemia (CLL) changes into a fast-growing type of lymphoma. Symptoms of Richter transformation include fever, loss of weight and muscle mass, and other health problems. Also called Richter syndrome.

rifampin  
A drug used in the treatment of infections caused by bacteria. It belongs to the family of drugs called antibiotics.

risedronate  (ris-ED-roe-nate)
A substance that is being studied in the prevention and treatment of osteoporosis. It belongs to the family of drugs called bone resorption inhibitors.

risk factor  
Something that may increase the chance of developing a disease. Some examples of risk factors for cancer include age, a family history of certain cancers, use of tobacco products, certain eating habits, obesity, lack of exercise, exposure to radiation or other cancer-causing agents, and certain genetic changes.

ritonavir  
A drug that belongs to the family of drugs called protease inhibitors. It interferes with the ability of a virus to make copies of itself.

ritual  (RIH-chuh-wul)
In medicine, a repeated action (such as hand washing) done to relieve feelings of fear, dread, and uneasiness. This is often seen in people who have an obsessive-compulsive disorder.

Rituxan  (rih-TUK-sun)
A monoclonal antibody used to treat certain types of B-cell non-Hodgkin lymphoma. Monoclonal antibodies are made in the laboratory and can locate and bind to substances in the body, including cancer cells. Rituxan binds to the protein called CD20, which is found on B-cells. Also called rituximab.

rituximab  (rih-TUK-sih-mab)
A monoclonal antibody used to treat certain types of B-cell non-Hodgkin lymphoma. Monoclonal antibodies are made in the laboratory and can locate and bind to substances in the body, including cancer cells. Rituximab binds to the protein called CD20, which is found on B-cells. Also called Rituxan.

RK-0202  
A substance that is being studied in the prevention of oral mucositis in patients receiving radiation therapy or chemotherapy for head and neck cancer.

RMP-7  
A substance that is being studied for its ability to help other drugs reach the brain. It belongs to the family of drugs called bradykinin agonists. Also called lobradimil.

RNA  
Ribonucleic acid. One of the two types of nucleic acids found in all cells. In the cell, RNA is made from DNA (the other type of nucleic acid), and proteins are made from RNA. Also called ribonucleic acid.

Ro 31-7453  
A substance that is being studied in the treatment of cancer. It may prevent cancer cells from dividing. It belongs to the family of drugs called cell cycle inhibitors.

Ro 50-3821  
A substance that is being studied in the treatment of anemia in patients who are receiving chemotherapy. It is a form of erythropoietin (a substance produced in the kidneys that stimulates the production of red blood cells) that has been changed in the laboratory. Also called methoxypolyethylene glycol epoetin beta.

rofecoxib  (ROH-feh-COK-sib)
A drug that was being used for pain relief and was being studied for its ability to prevent cancer and to block the growth of new blood vessels needed for tumors to grow. It is a type of nonsteroidal anti-inflammatory drug. Rofecoxib was taken off the market in the U.S. because of safety concerns. Also called Vioxx.

Roman chamomile  (ROH-mun KA-muh-mile)
A type of chamomile plant with daisy-like white flowers that is found in Europe, North America, and Argentina. The dried flowers are used in teas to calm and relax, to improve sleep, and to help with stomach problems. Its essential oil (scented liquid taken from plants) is used in perfumes, shampoos, face creams, lotions, and aromatherapy. The scientific names are Chamaemelum nobile and Anthemis nobilis. Also called English chamomile.

romidepsin  (ROH-mih-DEP-sin)
A substance being studied in the treatment of cancer. Romidepsin is a type of depsipeptide and histone deacetylase inhibitor. Also called FR901228.

ropivacaine  (roh-PIH-vuh-kayn)
A drug used to control pain and to cause a temporary loss of feeling in one part of the body, during and after surgery. It is also being studied for pain control after cancer surgery. It is a type of local anesthetic. Also called ropivacaine hydrochloride and Naropin.

ropivacaine hydrochloride  (roh-PIH-vuh-kayn HY-droh-KLOR-ide)
A drug used to control pain and to cause a temporary loss of feeling in one part of the body, during and after surgery. It is also being studied for pain control after cancer surgery. It is a type of local anesthetic. Also called ropivacaine and Naropin.

rosiglitazone  (roh-sig-LIH-tuh-zone)
The active ingredient in a drug that helps control the amount of glucose (sugar) in the blood and is being studied in the prevention and treatment of some types of cancer. Rosiglitazone stops cells from growing and may block the growth of new blood vessels that tumors need to grow. It is a type of thiazolidinedione and a type of antiangiogenesis agent.

rosiglitazone maleate  (roh-sig-LIH-tuh-zone MAY-lee-AYT)
A drug that helps control the amount of glucose (sugar) in the blood and is being studied in the prevention and treatment of some types of cancer. Rosiglitazone maleate stops cells from growing and may block the growth of new blood vessels that tumors need to grow. It is a type of thiazolidinedione and a type of antiangiogenesis agent. Also called Avandia.

RPI.4610  
A substance that is being studied in the treatment of kidney cancer. It may prevent the growth of blood vessels from surrounding tissue to the tumor. It belongs to the families of drugs called VEGF receptor and angiogenesis inhibitors. Also called Angiozyme.

RPR 109881A  
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called taxanes.

RSR13  
A substance being studied for its ability to increase the effectiveness of radiation therapy. It is a type of radiosensitizer. Also called efaproxiral.

RSV  
Respiratory syncytial virus. A virus that causes respiratory infections with cold-like symptoms. Also called respiratory syncytial virus.

RTA 744  
A substance being studied in the treatment of adult brain tumors. RTA 744 crosses the blood-brain barrier and blocks an enzyme needed for cancer growth. RTA 744 is a type of topoisomerase inhibitor. Also called topoisomerase II inhibitor RTA 744.

RU 486  
A drug used to end early pregnancies. It is also being studied in the treatment of some types of cancer and other conditions. RU 486 blocks the action of progesterone, a hormone that helps some cancers grow. It is a type of antiprogesterone. Also called mifepristone and Mifeprex.

Rubex  (ROO-bex)
A drug that is used to treat many types of cancer and is being studied in the treatment of other types of cancer. Rubex comes from the bacterium Streptomyces peucetius. It damages DNA (the molecules inside cells that carry genetic information) and stops cells from growing. Rapidly growing tumor cells that take up Rubex may die. It is a type of anthracycline antitumor antibiotic. Also called doxorubicin hydrochloride, doxorubicin, Adriamycin PFS, and Adriamycin RDF.

rV-TRICOM  
A cancer vaccine made with a form of a vaccinia virus that does not cause disease in humans. It is being studied in the treatment of some types of cancer. The virus is changed in the laboratory to make human proteins that may help immune cells in the body kill tumor cells. Also called vaccinia-TRICOM vaccine and recombinant vaccinia-TRICOM vaccine.

Back to Top

A Service of the National Cancer Institute
Department of Health and Human Services National Institutes of Health USA.gov