NCI Dictionary of Cancer Terms

The NCI Dictionary of Cancer Terms features 8,381 terms related to cancer and medicine.

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351 results found for: R

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.
R788 sodium: listen (… SOH-dee-um); A drug used to treat thrombocytopenia (low platelet levels) in patients with chronic immune thrombocytopenic purpura (ITP) that did not get better with other treatment. ITP is a condition in which platelets are destroyed by the immune system. R788 sodium is also being studied in the treatment of other conditions and types of cancer. It blocks an enzyme called Syk, which may help keep the immune system from destroying platelets. R788 sodium is a type of tyrosine kinase inhibitor. Also called fostamatinib disodium, Syk kinase inhibitor R-935788, and Tavalisse.
rabies: listen (RAY-beez); 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.
race: In biology, a term used to describe a group of people who share similar physical characteristics or genetic traits. These may include skin, hair, and eye color, facial features, and body type. Examples of races include Blacks and Caucasians. Some diseases or genetic conditions may be more common in certain races than in others.
rachitis: listen (ray-KY-tis); A condition in children in which bones become soft and deformed because they don’t have enough calcium and phosphorus. It is caused by not having enough vitamin D in the diet or by not getting enough sunlight. In adults, this condition is called osteomalacia. Also called infantile rickets, juvenile rickets, and rickets.
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 ACN53, recombinant adenovirus-p53, and SCH-58500.
RAD001: A drug used with exemestane to treat some postmenopausal women with advanced breast cancer that is hormone receptor positive and HER2 negative. It is also used to treat advanced renal cell carcinoma (a type of kidney cancer) and certain types of pancreatic, lung, and gastrointestinal neuroendocrine tumors. It is used under the brand name Afinitor to treat these cancers and to treat renal angiomyolipoma (a type of benign kidney tumor) and subependymal giant cell astrocytoma (SEGA, a type of benign brain tumor) in patients who have tuberous sclerosis. RAD001 is also used under the brand name Afinitor Disperz to treat SEGA and certain types of seizures in patients who have tuberous sclerosis. It is also used under the brand name Zortress to keep the body from rejecting a kidney or liver transplant. RAD001 is also being studied in the treatment of other conditions and types of cancer. It blocks a protein involved in cell division, which may help keep abnormal cells, including cancer cells, from growing. It may also prevent the growth of new blood vessels that tumors need to grow. RAD001 also lowers the body’s immune response. It is a type of kinase inhibitor, a type of angiogenesis inhibitor, and a type of immunosuppressant. Also called everolimus.
radiation: listen (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 can damage cells. It is used to diagnose and treat some types of cancer.
radiation brachytherapy: listen (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, implant radiation therapy, and internal radiation therapy.
radiation cystitis: listen (RAY-dee-AY-shun sis-TY-tis); Inflammation of the lining of the bladder caused by radiation therapy to the pelvis, including the bladder. Symptoms include pain and a burning feeling while urinating, blood in the urine, feeling a need to urinate often or right away, being unable to control the flow of urine, bladder spasms, and pain in the pelvis. Some symptoms of radiation cystitis may go away after radiation therapy has ended, but others may continue over time.
radiation dermatitis: listen (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: listen (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 fibrosis: listen (RAY-dee-AY-shun fy-BROH-sis); The formation of scar tissue as a result of radiation therapy.
radiation necrosis: listen (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: listen (RAY-dee-AY-shun nurs); A health professional who specializes in caring for people who are receiving radiation therapy.
radiation oncologist: listen (RAY-dee-AY-shun on-KAH-loh-jist); A doctor who has special training in using radiation to treat cancer.
radiation physicist: listen (RAY-dee-AY-shun FIH-zih-sist); 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 poisoning: listen (RAY-dee-AY-shun POY-zuh-ning); Serious illness caused by being exposed to high doses of certain types of radiation, usually over a short period of time. Symptoms of radiation poisoning usually occur right after exposure but they may happen over time, and they may come and go. Symptoms include nausea and vomiting, diarrhea, headache, dizziness, weakness, fatigue, bleeding, hair loss, swelling, itching, and redness of the skin, and other skin problems. Very large doses of radiation may cause death. Also called acute radiation sickness, acute radiation syndrome, radiation sickness, and radiation sickness syndrome.
radiation sickness: listen (RAY-dee-AY-shun SIK-nes); Serious illness caused by being exposed to high doses of certain types of radiation, usually over a short period of time. Symptoms of radiation sickness usually occur right after exposure but they may happen over time, and they may come and go. Symptoms include nausea and vomiting, diarrhea, headache, dizziness, weakness, fatigue, bleeding, hair loss, swelling, itching, and redness of the skin, and other skin problems. Very large doses of radiation may cause death. Also called acute radiation sickness, acute radiation syndrome, radiation poisoning, and radiation sickness syndrome.
radiation sickness syndrome: listen (RAY-dee-AY-shun SIK-nes SIN-drome); Serious illness caused by being exposed to high doses of certain types of radiation, usually over a short period of time. Symptoms of radiation sickness syndrome usually occur right after exposure but they may happen over time, and they may come and go. Symptoms include nausea and vomiting, diarrhea, headache, dizziness, weakness, fatigue, bleeding, hair loss, swelling, itching, and redness of the skin, and other skin problems. Very large doses of radiation may cause death. Also called acute radiation sickness, acute radiation syndrome, radiation poisoning, and radiation sickness.
radiation surgery: listen (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 radiosurgery, stereotactic radiosurgery, and stereotaxic radiosurgery.
radiation therapist: listen (RAY-dee-AY-shun THAYR-uh-pist); A health professional who gives radiation treatment.
radiation therapy: listen (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 or brachytherapy). 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 irradiation and radiotherapy.
radical cervicectomy: listen (RA-dih-kul SER-vih-SEK-toh-mee); Surgery to remove the cervix, nearby tissue and lymph nodes, and the upper part of the vagina. It may be used to treat women with early-stage cervical cancer who want to have children. After the cervix is removed, the uterus is attached to the remaining part of the vagina. A special stitch or band is used to act as the cervix and create an opening to the uterus. The stitch or band may be opened or closed as needed. Also called radical trachelectomy.
radical cystectomy: listen (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: listen (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: listen (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: listen (RA-dih-kul limf node dy-SEK-shun); 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: listen (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: listen (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: listen (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: listen (RA-dih-kul PROS-tuh-TEK-toh-mee); Surgery to remove the entire prostate and some of the tissue around it. Nearby lymph nodes may also be removed. In a radical retropubic prostatectomy, an incision (cut) is made in the wall of the lower abdomen. In a radical perineal prostatectomy, an incision (cut) is made in the perineum (the area between the anus and scrotum). In a laparoscopic radical prostatectomy, several small incisions (cuts) are made in the wall of the abdomen. A laparoscope (a thin, tube-like instrument with a light and lens for viewing) is inserted through one opening to guide the surgery. Surgical instruments are inserted through the other openings to do the surgery.
radical retropubic prostatectomy: listen (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 trachelectomy: listen (RA-dih-kul TRAY-kee-LEK-toh-mee); Surgery to remove the cervix, nearby tissue and lymph nodes, and the upper part of the vagina. It may be used to treat women with early-stage cervical cancer who want to have children. After the cervix is removed, the uterus is attached to the remaining part of the vagina. A special stitch or band is used to act as the cervix and create an opening to the uterus. The stitch or band may be opened or closed as needed. Also called radical cervicectomy.
radical vulvectomy: listen (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.
radio wave: listen (RAY-dee-oh…); A type of wave made when an electric field and a magnetic field are combined. Radio waves are being studied in the treatment of several types of cancer and other conditions. The radio waves are sent through needles inserted into tumor tissue and may kill cancer cells. Radio waves are also used in MRI to create detailed images of areas inside the body.
radioactive: listen (RAY-dee-oh-AK-tiv); Giving off radiation.
radioactive drug: listen (RAY-dee-oh-AK-tiv...); A drug that contains a radioactive substance and is used to diagnose or treat disease, including cancer. Also called radiopharmaceutical.
radioactive fallout: listen (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 glucose: listen (RAY-dee-oh-AK-tiv GLOO-kose); A radioactive form of glucose (sugar) often used during a positive emission tomography (PET) scan, a type of imaging test. In PET, a small amount of radioactive glucose is injected into a vein, and a scanner makes a picture of where the glucose is being used in the body. Cancer cells show up brighter in the picture because they are more active and take up more glucose than normal cells do. When used with PET, radioactive glucose helps find cancer cells in the body.
radioactive iodine: listen (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: listen (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: listen (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.
radioembolization: listen (RAY-dee-oh-EM-boh-lih-ZAY-shun); A type of radiation therapy used to treat liver cancer or cancer that has spread to the liver. A thin, flexible tube is used to inject tiny beads that hold the radioactive substance yttrium Y 90 into the main blood vessel that carries blood to the liver. The beads collect in the tumor and in blood vessels near the tumor, and the yttrium Y 90 gives off radiation. This destroys the blood vessels that the tumor needs to grow and kills the cancer cells. Radioembolization is a type of internal radiation therapy. Also called intra-arterial brachytherapy.
radiofrequency ablation: listen (RAY-dee-oh-FREE-kwen-see a-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.
radiofrequency radiation: listen (RAY-dee-oh-FREE-kwen-see RAY-dee-AY-shun); A type of low-energy radiation. The most common sources of radiofrequency radiation are wireless and cellular telephones, radios, televisions, radar, satellites, microwave ovens, computers, and wireless networks (Wi-Fi). Although there have been health concerns, most types of radiofrequency radiation have not been found to cause harmful health effects, including cancer. Radiofrequency radiation is a type of non-ionizing electromagnetic radiation.
radioimaging: listen (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. Also called nuclear medicine scan.
radioimmunoconjugate: listen (RAY-dee-oh-IH-myoo-noh-KON-jih-gut); A radioactive substance that carries radiation directly to cancer cells. A radioimmunoconjugate is made by attaching a radioactive molecule to an immune substance, such as a monoclonal antibody, that can bind to cancer cells. This may help kill cancer cells without harming normal cells. Radioimmunoconjugates may also be used with imaging to help find cancer cells in the body.
radioimmunodiagnostics: listen (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: listen (RAY-dee-oh-IH-myoo-noh-GY-ded SER-juh-ree); A procedure that uses radioactive substances to locate tumors so that they can be removed by surgery.
radioimmunotherapeutics: listen (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: listen (RAY-dee-oh-IH-myoo-noh-THAYR-uh-pee); A type of radiation therapy in which a radioactive substance is linked to a monoclonal antibody and injected into the body. The monoclonal antibody can bind to substances in the body, including cancer cells. The radioactive substance gives off radiation, which may help kill cancer cells. Radioimmunotherapy is being used to treat some types of cancer, such as lymphoma.
radioisotope: listen (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: listen (RAY-dee-oh-LAY-buld); Any compound that has been joined with a radioactive substance.
radiologic exam: listen (RAY-dee-oh-LAH-jik eg-ZAM); A test that uses radiation or other imaging procedures to find signs of cancer or other abnormalities.
radiologist: listen (RAY-dee-AH-loh-jist); 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.
radiology: listen (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: listen (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: listen (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: listen (RAY-dee-oh-FAR-muh-SOO-tih-kul); A drug that contains a radioactive substance and is used to diagnose or treat disease, including cancer. Also called radioactive drug.
radioprotective agent: listen (RAY-dee-oh-proh-TEK-tiv AY-jent); A type of drug that helps protect healthy tissue from some of the side effects caused by radiation therapy. For example, a drug called amifostine helps reduce dry mouth in patients receiving radiation therapy for head and neck cancer.
radiosensitization: listen (RAY-dee-oh-SEN-sih-tih-ZAY-shun); The use of a drug that makes tumor cells more sensitive to radiation therapy.
radiosensitizer: listen (RAY-dee-oh-SEN-sih-TY-zer); Any substance that makes tumor cells easier to kill with radiation therapy. Some radiosensitizers are being studied in the treatment of cancer. Also called radiosensitizing agent.
radiosensitizing agent: listen (RAY-dee-oh-SEN-sih-TY-zing AY-jent); Any substance that makes tumor cells easier to kill with radiation therapy. Some radiosensitizing agents are being studied in the treatment of cancer. Also called radiosensitizer.
radiosurgery: listen (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 radiation surgery, stereotactic radiosurgery, and stereotaxic radiosurgery.
radiotherapy: listen (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 or brachytherapy). Systemic radiotherapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Also called irradiation and radiation therapy.
radium Ra 223-dichloride: listen (RAY-dee-um … dy-KLOR-ide); A drug used to treat prostate cancer that has spread to the bone and is causing symptoms but has not spread to other organs. It is used in patients whose cancer is castration resistant (has not responded to treatments that lower testosterone levels). It is also being studied in the treatment of other types of cancer. Radium Ra 223-dichloride contains a radioactive substance called radium Ra 223. It collects in bone and gives off radiation that may kill cancer cells. Also called Xofigo.
radon: listen (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: listen (RAF-tih-lose SIH-ner-jee ...); 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 substances that 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: listen (ra-LOK-sih-feen); The active ingredient in a drug 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. Raloxifene is also being studied in the treatment of other types of cancer. It blocks the effects of the hormone estrogen in breast tissue, which may help keep breast cancer cells from growing. It may also help keep bone from breaking down. Raloxifene is a type of selective estrogen receptor modulator (SERM).
raloxifene hydrochloride: listen (ra-LOK-sih-feen HY-droh-KLOR-ide); A drug 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. Raloxifene hydrochloride is also being studied in the treatment of other types of cancer. It blocks the effects of the hormone estrogen in breast tissue, which may help keep breast cancer cells from growing. It may also help keep bone from breaking down. Raloxifene hydrochloride is a type of selective estrogen receptor modulator (SERM). Also called Evista.
raltitrexed: listen (RAL-tih-TREK-sed); 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.
ramucirumab: listen (RA-myoo-SIR-yoo-mab); A drug used with other drugs to treat colorectal cancer and non-small cell lung cancer that have spread to other parts of the body. It is used alone or with another drug to treat cancer of the stomach or gastroesophageal junction (area where the esophagus connects to the stomach) that is advanced or has spread to other parts of the body. It is also being studied in the treatment of other types of cancer. Ramucirumab binds to receptors for a protein called vascular endothelial growth factor (VEGF), which may be found on some types of cancer cells. This may prevent the growth of new blood vessels that tumors need to grow. Ramucirumab is a type of antiangiogenesis agent and a type of monoclonal antibody. Also called anti-VEGFR-2 fully human monoclonal antibody IMC-1121B, Cyramza, and IMC-1121B.
randomization: listen (RAN-duh-mih-ZAY-shun); 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: listen (RAN-duh-mized KLIH-nih-kul TRY-ul); A study in which the participants are divided by chance into separate groups that compare different treatments or other interventions. Using chance to divide people into groups means that the groups will be similar and that the effects of the treatments they receive can be compared more fairly. At the time of the trial, it is not known which treatment is best.
ranpirnase: listen (RAN-per-nays); A substance being studied in the treatment of cancer. It is a type of ribonuclease enzyme. Also called Onconase.
Rapamune: listen (RA-puh-MYOON); A drug used to keep the body from rejecting organ and bone marrow transplants. Rapamune blocks certain white blood cells that can reject foreign tissues and organs. It also blocks a protein that is involved in cell division. It is a type of antibiotic, a type of immunosuppressant, and a type of serine/threonine kinase inhibitor. Rapamune was previously called rapamycin. Also called sirolimus.
rapamycin: listen (RA-puh-MY-sin); A drug used to keep the body from rejecting organ and bone marrow transplants. Rapamycin blocks certain white blood cells that can reject foreign tissues and organs. It also blocks a protein that is involved in cell division. It is a type of antibiotic, a type of immunosuppressant, and a type of serine/threonine kinase inhibitor. Rapamycin is now called sirolimus.
rapid eye movement sleep: listen (RA-pid I MOOV-ment 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: listen (RA-pid HOR-mone SY-kuh-ling); 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: listen (… OH-pee-OYD); A substance that acts quickly to treat moderate to severe pain. Opioids are like opiates, such as morphine and codeine, but are not made from opium. Opioids bind to opioid receptors in the central nervous system. A rapid-onset opioid is a type of alkaloid.
RARA gene: listen (… jeen); A gene that makes a protein called retinoic acid receptor alpha (RARA), which controls the activity of certain genes that help white blood cells mature. Mutations (changes) in the RARA gene can occur when a piece of the chromosome containing the RARA gene breaks off and joins with a gene called PML on another chromosome. These changes may cause too many immature white blood cells to build up in the blood and bone marrow. This can lead to an aggressive (fast-growing) type of acute myeloid leukemia called acute promyelocytic leukemia. The protein made by the RARA gene is a type of transcription factor. Also called retinoic acid receptor alpha gene.
rare cancer: listen (rayr KAN-ser); As defined by the National Cancer Institute, cancer that occurs in fewer than 15 out of 100,000 people each year. Most types of cancer are considered rare, and they are often more difficult to prevent, diagnose, and treat than the more common cancers. Because there are fewer cases, research is difficult. Examples of rare cancers are anal, stomach, and laryngeal cancer.
RAS gene family: listen (... jeen FA-mih-lee); A family of genes that make proteins involved in cell signaling pathways that control cell growth and cell death. Mutated (changed) forms of the RAS gene may be found in some types of cancer. These changes may cause cancer cells to grow and spread in the body. Members of the RAS gene family include KRAS, HRAS, and NRAS.
ras peptide: listen (ras 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: listen (ras-BUR-ih-kays); A drug used to treat high blood levels of uric acid in patients with leukemia, lymphoma, and other types of cancer who are receiving certain types of cancer treatment. It is also being studied in the treatment of other medical conditions. Rasburicase is a type of recombinant enzyme and a type of urate-lowering drug. Also called Elitek and recombinant urate oxidase.
rattlesnake root: listen (RA-til-SNAYK 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, bugbane, and bugwort.
rauschpfeffer: listen (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 intoxicating pepper, kava kava, 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: listen (RA-vuh-KAH-nuh-zole); A substance that is being studied in the treatment of infections caused by fungi. It belongs to the family of drugs called antifungal agents.
ravulizumab: (RAV-yoo-LIZ-yoo-mab); A drug used to treat a rare red blood cell disorder called paroxysmal nocturnal hemoglobinuria (PNH). It is also being studied in the treatment of other conditions. Ravulizumab binds to an immune system protein called C5. This may help keep red blood cells from breaking down. Ravulizumab is a type of monoclonal antibody. Also called Ultomiris.
RBC: A type of blood cell that is made in the bone marrow and found in the blood. RBCs contain a protein called hemoglobin, which carries oxygen from the lungs to all parts of the body. Checking the number of RBCs in the blood is usually part of a complete blood cell (CBC) test. It may be used to look for conditions such as anemia, dehydration, malnutrition, and leukemia. Also called erythrocyte and red blood cell.
R-CHOP: listen; An abbreviation for a chemotherapy combination that is used to treat non-Hodgkin lymphoma and mantle cell lymphoma and is being studied in the treatment of other types of cancer. It includes the drugs rituximab, cyclophosphamide, doxorubicin hydrochloride (hydroxydaunorubicin), vincristine sulfate (Oncovin), and prednisone. Also called R-CHOP regimen.
R-CHOP regimen: listen (… REH-jih-men); An abbreviation for a chemotherapy combination that is used to treat non-Hodgkin lymphoma and mantle cell lymphoma and is being studied in the treatment of other types of cancer. It includes the drugs rituximab, cyclophosphamide, doxorubicin hydrochloride (hydroxydaunorubicin), vincristine sulfate (Oncovin), and prednisone. Also called R-CHOP.
R-CVP: An abbreviation for a chemotherapy combination used to treat indolent (slow-growing) non-Hodgkin lymphoma. It includes the drugs rituximab, cyclophosphamide, vincristine sulfate, and prednisone. Also called R-CVP regimen.
R-CVP regimen: listen (… REH-jih-men); An abbreviation for a chemotherapy combination used to treat indolent (slow-growing) non-Hodgkin lymphoma. It includes the drugs rituximab, cyclophosphamide, vincristine sulfate, and prednisone. Also called R-CVP.
reactivate: listen (ree-AK-tih-VAYT); To make active again or make something work again. In medicine, an infection or a disease is described as reactivated when it comes back after a period with no signs of disease.
reactive oxygen species: listen (ree-AK-tive OK-sih-jen SPEE-sees); A type of unstable molecule that contains oxygen and that easily reacts with other molecules in a cell. A build up of reactive oxygen species in cells may cause damage to DNA, RNA, and proteins, and may cause cell death. Reactive oxygen species are free radicals. Also called oxygen radical.
reagent: listen (ree-AY-jent); A substance used to carry out a laboratory test. Reagents may be used in a chemical reaction to detect, measure, or make other substances.
rebeccamycin: listen (reh-BEH-kuh-MY-sin); A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called antineoplastic antibiotics.
rebeccamycin analog: listen (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: listen (reh-SEN-tin); A substance being studied in the treatment of some types of cancer. Recentin may prevent the growth of new blood vessels that tumors need to grow and may kill cancer cells. It is a type of antiangiogenesis agent and a type of vascular endothelial growth factor (VEGF) receptor tyrosine kinase inhibitor. Also called AZD2171 and cediranib maleate.
receptor: listen (reh-SEP-ter); A molecule inside or on the surface of a cell that binds to a specific substance and causes a specific effect in the cell.
recipient: listen (reh-SIH-pee-ent); In medicine, a person who receives blood, cells, tissue, or an organ from another person, such as in a blood transfusion or an organ transplant.
RECIST: listen; A standard way to measure how well a cancer patient 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 patient can have are a complete response (CR), a partial response (PR), progressive disease (PD), and stable disease (SD). Also called Response Evaluation Criteria In Solid Tumors.
recombinant: listen (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: listen (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 ACN53, rAd/p53, and SCH-58500.
recombinant fowlpox-CEA-MUC-1-TRICOM vaccine: listen (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: listen (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-11: listen (ree-KOM-bih-nunt HYOO-mun in-ter-LOO-kin...); A drug used to increase the number of blood cells, especially platelets, in some cancer patients receiving chemotherapy. Recombinant human interleukin-11 is a form of interleukin-11 (a cytokine normally made by support cells in the bone marrow) that is made in the laboratory. It is a type of biological response modifier. Also called Neumega, oprelvekin, and rhIL-11.
recombinant human interleukin-2: listen (ree-KOM-bih-nunt HYOO-mun in-ter-LOO-kin...); A drug used to treat melanoma and renal cell carcinoma (a type of kidney cancer) that have spread to other parts of the body. It is also being studied in the treatment of other types of cancer. Recombinant human interleukin-2 is a form of interleukin-2 that is made in the laboratory. Recombinant human interleukin-2 increases the activity and growth of T lymphocytes and B lymphocytes (types of white blood cells). This may help the immune system kill cancer cells. Recombinant human interleukin-2 is a type of biological response modifier. Also called aldesleukin and Proleukin.
recombinant human methionyl stem cell factor: listen (ree-KOM-bih-nunt HYOO-mun meh-THY-oh-nil stem sel FAK-ter); A substance that causes blood stem cells (cells from which other types of cells develop) to change into different types of blood cells and increases the number and actions of these cells in the blood. It is being studied in the treatment of myelodysplasia. Recombinant human methionyl stem cell factor is a type of recombinant stem cell growth factor. Also called ancestim, r-metHuSCF, and Stemgen.
recombinant human papillomavirus bivalent vaccine: listen (ree-KOM-bih-nunt HYOO-mun PA-pih-LOH-muh-VY-rus by-VAY-lent vak-SEEN); A vaccine used to prevent cervical cancer caused by human papillomavirus (HPV) types 16 and 18. It is also used to prevent lesions that may lead to cervical cancer. Recombinant human papillomavirus bivalent vaccine is approved for use in females aged 9 to 25 years. It is a type of bivalent vaccine (a vaccine that works against two different viruses or other microorganisms). Also called Cervarix.
recombinant human papillomavirus nonavalent vaccine: listen (ree-KOM-bih-nunt HYOO-mun PA-pih-LOH-muh-VY-rus NOH-nuh-VAY-lent vak-SEEN); A vaccine used to prevent anal, cervical, vaginal, and vulvar cancer caused by human papillomavirus (HPV) types 16, 18, 31, 33, 45, 52, and 58 and genital warts caused by HPV types 6 and 11. It is also used to prevent lesions that may lead to anal, cervical, vaginal, or vulvar cancer. Recombinant human papillomavirus nonavalent vaccine is approved for use in females and males aged 9 to 26 years. It is a type of nonavalent vaccine (a vaccine that works against nine different viruses or other microorganisms). Also called Gardasil 9.
recombinant human papillomavirus quadrivalent vaccine: listen (ree-KOM-bih-nunt HYOO-mun PA-pih-LOH-muh-VY-rus KWAH-drih-VAY-lent vak-SEEN); A vaccine used to prevent anal, cervical, vaginal, and vulvar cancer caused by human papillomavirus (HPV) types 16 and 18 and genital warts caused by HPV types 6 and 11. It is also used to prevent lesions that may lead to anal, cervical, vaginal, or vulvar cancer. Recombinant human papillomavirus quadrivalent vaccine is approved for use in males and females aged 9 to 26 years. It is a type of quadrivalent vaccine (a vaccine that works against four different viruses or other microorganisms). Also called Gardasil.
recombinant interferon alfa-2b: listen (ree-KOM-bih-nunt in-ter-FEER-on AL-fuh …); A drug used to treat AIDS-related Kaposi sarcoma in certain patients, hairy cell leukemia, and melanoma that has been removed by surgery. It is also used with other anticancer drugs to treat a certain type of non-Hodgkin lymphoma. Recombinant interferon alfa-2b is also used to treat some infections caused by viruses, such as the hepatitis C virus. It is being studied in the treatment of other types of cancer and other conditions. Recombinant interferon alfa-2b is a form of interferon alfa (a substance normally made by cells in the immune system) and is made in the laboratory. It is a type of cytokine and a type of biological response modifier. Also called IFN alpha-2B, interferon alfa-2b, and Intron A.
recombinant tissue plasminogen activator: listen (ree-KOM-bih-nunt TIH-shoo plaz-MIN-oh-jen AK-tih-vay-ter); 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 Activase, Alteplase, and r-tPA.
recombinant urate oxidase: listen (ree-KOM-bih-nunt YOOR-ayt OK-sih-days); A drug used to treat high blood levels of uric acid in patients with leukemia, lymphoma, and other types of cancer who are receiving certain types of cancer treatment. It is also being studied in the treatment of other medical conditions. Recombinant urate oxidase is a type of recombinant enzyme and a type of urate-lowering drug. Also called Elitek and rasburicase.
recombinant vaccinia-CEA-MUC-1-TRICOM vaccine: listen (ree-KOM-bih-nunt vak-SIH-nee-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: listen (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 rV-TRICOM and vaccinia-TRICOM vaccine.
reconstructive surgeon: listen (REE-kun-STRUK-tiv SER-jun); 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: listen (REE-kun-STRUK-tiv SER-juh-ree); Surgery that is done to reshape or rebuild (reconstruct) a part of the body changed by previous surgery.
recover: listen (ree-KUH-ver); To become well and healthy again.
recreational therapy: listen (REH-kree-AY-shuh-nul 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: listen (REK-tul); By or having to do with the rectum. The rectum is the last several inches of the large intestine closest to the anus.
rectal cancer: listen (REK-tul KAN-ser); Cancer that forms in the tissues of the rectum (the last several inches of the large intestine closest to the anus).
rectal reconstruction: listen (REK-tul REE-kun-STRUK-shun); Surgery to rebuild the rectum (the last several inches of the large intestine before the anus) using a section of the colon. This may be done when the rectum has been removed to treat cancer or other diseases.
rectitis: listen (rek-TY-tis); Inflammation of the mucous membrane that lines the rectum (the last several inches of the large intestine closest to the anus). Also called proctitis.
rectum: listen (REK-tum); The last several inches of the large intestine closest to the anus.
recur: listen (ree-KER); To come back or to return.
recurrence: listen (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: listen (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.
recurrent respiratory papillomatosis: listen (ree-KER-ent RES-pih-ruh-TOR-ee PA-pih-LOH-muh-TOH-sis); A rare condition in which wart-like growths called papillomas grow in the respiratory tract (air passages leading from the nose and mouth into the lungs). The papillomas most often grow in the larynx (voice box) and vocal cords. They can grow quickly, and they often grow back after they have been removed by surgery. Signs and symptoms of recurrent respiratory papillomatosis include hoarseness, chronic cough, swallowing problems, and breathing problems, which may sometimes be life-threatening. Recurrent respiratory papillomatosis is caused by infection with certain types of human papillomavirus (HPV). It can occur in both children and adults. Also called RRP.
red blood cell: listen (red blud sel); A type of blood cell that is made in the bone marrow and found in the blood. Red blood cells contain a protein called hemoglobin, which carries oxygen from the lungs to all parts of the body. Checking the number of red blood cells in the blood is usually part of a complete blood cell (CBC) test. It may be used to look for conditions such as anemia, dehydration, malnutrition, and leukemia. Also called erythrocyte and RBC.
red cedar: listen (red 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: listen (red KLOH-ver); 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, Trifolium pratense, and wild clover.
red date: listen (red dayt); The fruit of the jujube plant. It has been used in some cultures to treat certain medical problems.
red elm: listen (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 gray elm, Indian elm, slippery elm, sweet elm, Ulmus fulva, and Ulmus rubra.
redox: listen (REE-dox); A chemical reaction that takes place between an oxidizing substance and a reducing substance. The oxidizing substance loses electrons in the reaction, and the reducing substance gains electrons. For example, rust forms when there is a redox reaction between oxygen contained in water or moist air (an oxidizing substance) and iron (a reducing substance). Redox reactions also occur when glucose (a type of sugar) and fat are broken down in the body to make energy. Also called oxidation-reduction.
reduction: listen (ree-DUK-shun); A chemical reaction that takes place when a substance comes into contact with hydrogen or another reducing substance.
Reed-Sternberg cell: listen (reed-STERN-berg sel); A type of cell that appears in people with Hodgkin disease. The number of these cells increases as the disease advances.
reference interval: listen (REH-frents IN-ter-vul); In medicine, a set of values that a doctor uses to interpret a patient’s test results. The reference interval for a given test is based on the results that are seen in 95% of the healthy population. Sometimes patients whose test results are outside of the reference interval may be healthy, and some patients whose test results are within the reference interval may have a health problem. The reference interval for a test may be different for different groups of people (for example, men and women). Also called normal range, reference range, and reference values.
reference range: listen (REH-frents raynj); In medicine, a set of values that a doctor uses to interpret a patient’s test results. The reference range for a given test is based on the results that are seen in 95% of the healthy population. Sometimes patients whose test results are outside of the reference range may be healthy, and some patients whose test results are within the reference range may have a health problem. The reference range for a test may be different for different groups of people (for example, men and women). Also called normal range, reference interval, and reference values.
reference values: listen (REH-frents VAL-yooz); In medicine, a set of values that a doctor uses to interpret a patient’s test results. The reference values for a given test are based on the results that are seen in 95% of the healthy population. Sometimes patients whose test results are outside of the reference values may be healthy, and some patients whose test results are within the reference values may have a health problem. The reference values for a test may be different for different groups of people (for example, men and women). Also called normal range, reference interval, and reference range.
referral: listen (reh-FER-ul); In medicine, the act of a doctor in which a patient is sent to another doctor for additional healthcare services.
reflexology: listen (ree-flek-SAH-loh-jee); A type of massage in which different amounts of pressure are applied to specific points on the feet or hands. These points are believed to match up with certain other parts of the body. Reflexology is claimed to cause relaxation and healing in those parts of the body, but this has not been proven.
reflux: listen (REE-fluks); The backward flow of liquid from the stomach into the esophagus.
refractory: listen (reh-FRAK-tor-ee); In medicine, describes a disease or condition that does not respond to treatment.
refractory cancer: listen (reh-FRAK-tor-ee KAN-ser); 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: listen (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: listen (ree-JEH-neh-RAY-shun); In biology, regrowth of damaged or destroyed tissue or body part.
regimen: listen (REH-jih-men); A treatment plan that specifies the dosage, the schedule, and the duration of treatment.
regional: listen (REE-juh-nul); In oncology, describes the body area right around a tumor.
regional anesthesia: listen (REE-juh-nul A-nes-THEE-zhuh); A temporary loss of feeling or awareness in a part of the body, such as an arm or a leg, caused by special drugs or other substances called anesthetics. The patient stays awake but has no feeling in the part of the body treated with the anesthetic.
regional cancer: listen (REE-juh-nul KAN-ser); Refers to cancer that has grown beyond the original (primary) tumor to nearby lymph nodes or organs and tissues.
regional chemotherapy: listen (REE-juh-nul KEE-moh-THAYR-uh-pee); Treatment with anticancer drugs directed to a specific area of the body.
regional enteritis: listen (REE-juh-nul EN-teh-RY-tis); A condition in which the gastrointestinal tract is inflamed over a long period of time. Regional enteritis usually affects the small intestine and colon. Symptoms include fever, diarrhea, stomach cramps, vomiting, and weight loss. Regional enteritis increases the risk of colorectal cancer and small intestine cancer. It is a type of inflammatory bowel disease (IBD). Also called Crohn disease.
regional lymph node: listen (REE-juh-nul limf node); In oncology, a lymph node that drains lymph from the region around a tumor.
regional lymph node dissection: listen (REE-juh-nul limf node dy-SEK-shun); 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: listen (...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: listen (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.
regorafenib: listen (REH-goh-RA-feh-nib); A drug used to treat hepatocellular carcinoma (a type of liver cancer) that was already treated with sorafenib (a type of anticancer drug). It is also used to treat colorectal cancer that has spread to other parts of the body and has not gotten better with other treatment. Regorafenib is also used to treat gastrointestinal stromal tumors (GIST) that cannot be removed by surgery or have spread to other parts of the body and have not gotten better with other anticancer drugs. It is being studied in the treatment of other types of cancer. Regorafenib blocks the action of certain proteins, which may help keep cancer cells from growing and may kill them. It may also prevent the growth of new blood vessels that tumors need to grow. Regorafenib is a type of kinase inhibitor and a type of antiangiogenesis agent. Also called Stivarga.
regression: listen (reh-GREH-shun); A decrease in the size of a tumor or in the extent of cancer in the body.
regulatory T cell: listen (REH-gyoo-luh-TOR-ee T sel); A type of immune cell that blocks the actions of some other types of lymphocytes, to keep the immune system from becoming over-active. Regulatory T cells are being studied in the treatment of cancer. A regulatory T cell is a type of white blood cell and a type of lymphocyte. Also called suppressor T cell, T reg, and T-regulatory cell.
rehabilitation: listen (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 services: listen (REE-huh-BIH-lih-TAY-shun SER-vih-ses); Special healthcare services that help a person regain physical, mental, and/or cognitive (thinking and learning) abilities that have been lost or impaired as a result of disease, injury, or treatment. Rehabilitation services help people return to daily life and live in a normal or near-normal way. These services may include physical therapy, occupational therapy, speech and language therapy, cognitive therapy, and mental health rehabilitation services.
rehabilitation specialist: listen (REE-huh-BIH-lih-TAY-shun SPEH-shuh-list); 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: listen (REE-laps); The return of a disease or the signs and symptoms of a disease after a period of improvement. Relapse also refers to returning to the use of an addictive substance or behavior, such as cigarette smoking.
relapse-free survival: listen (REE-laps … ser-VY-vul); In cancer, the length of time after primary treatment for a cancer ends that the patient survives without any signs or symptoms of that cancer. In a clinical trial, measuring the relapse-free survival is one way to see how well a new treatment works. Also called DFS, disease-free survival, and RFS.
relative odds: listen (REH-luh-tiv …); A measure of the odds of an event happening in one group compared to the odds of the same event happening in another group. In cancer research, relative odds are most often used in case-control (backward looking) studies to find out if being exposed to a certain substance or other factor increases the risk of cancer. For example, researchers may study a group of individuals with cancer (cases) and another group without cancer (controls) to see how many people in each group were exposed to a certain substance or factor. They calculate the odds of exposure in both groups and then compare the odds. A relative odds of one means that both groups had the same odds of exposure and, therefore, the exposure probably does not increase the risk of cancer. A relative odds of greater than one means that the exposure may increase the risk of cancer, and a relative odds of less than one means that the exposure may reduce the risk of cancer. Also called odds ratio.
relative risk: listen (REH-luh-tiv …); A measure of the risk of a certain event happening in one group compared to the risk of the same event happening in another group. In cancer research, relative risk is used in prospective (forward looking) studies, such as cohort studies and clinical trials. A relative risk of one means there is no difference between two groups in terms of their risk of cancer, based on whether or not they were exposed to a certain substance or factor, or how they responded to two treatments being compared. A relative risk of greater than one or of less than one usually means that being exposed to a certain substance or factor either increases (relative risk greater than one) or decreases (relative risk less than one) the risk of cancer, or that the treatments being compared do not have the same effects. Also called risk ratio.
relative survival rate: listen (REH-luh-tiv ser-VY-vul …); A way of comparing the survival of people who have a specific disease with those who don’t, over a certain period of time. This is usually five years from the date of diagnosis or the start of treatment for those with the disease. It is calculated by dividing the percentage of patients with the disease who are still alive at the end of the period of time by the percentage of people in the general population of the same sex and age who are alive at the end of the same time period. The relative survival rate shows whether the disease shortens life.
relaxation technique: listen (ree-lak-SAY-shun tek-NEEK); A method used to help reduce muscle tension and stress, lower blood pressure, and control pain. Examples of relaxation techniques include tensing and relaxing muscles throughout the body, guided imagery (focusing the mind on positive images), meditation (focusing thoughts), and deep breathing exercises.
relaxation therapy: listen (ree-lak-SAY-shun THAYR-uh-pee); A type of therapy that helps reduce muscle tension and stress, lowers blood pressure, and controls pain. It may involve tensing and relaxing muscles throughout the body. It may be used with guided imagery (focusing the mind on positive images) and meditation (focusing thoughts).
Relenza: listen (reh-LEN-zuh); A drug used to prevent and to treat influenza virus infections. It blocks the release of the virus from infected cells. It is a type of antiviral agent. Also called zanamivir.
religion: listen (reh-LIH-jun); A set of beliefs and practices that center on questions about the meaning of life and may involve the worship of a supreme being.
Relistor: listen (REH-lih-stor); A drug used to relieve constipation caused by treatment with opioids (pain killers similar to morphine). It is used in patients with pain caused by cancer or treatment for cancer or by other advanced disease. 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: listen (… 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: listen (REH-meh-ron); A drug used to treat depression. Remeron increases the levels of the chemicals serotonin and norepinephrine in the brain, which helps improve mood. It is a type of antidepressant. Also called mirtazapine.
remission: listen (reh-MIH-shun); 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: listen (reh-MIH-shun in-DUK-shun THAYR-uh-pee); Initial treatment with anticancer drugs to decrease the signs or symptoms of cancer or make them disappear.
remote brachytherapy: listen (ree-MOTE BRAY-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 and high-dose-rate remote radiation therapy.
renal artery: listen (REE-nul 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: listen (REE-nul KAP-sul); The fibrous connective tissue that surrounds each kidney.
renal cell adenocarcinoma: listen (REE-nul sel A-deh-noh-KAR-sih-NOH-muh); 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 cell cancer, and renal cell carcinoma.
renal cell cancer: listen (REE-nul sel KAN-ser); 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 cell adenocarcinoma, and renal cell carcinoma.
renal cell carcinoma: listen (REE-nul sel KAR-sih-NOH-muh); 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 cell adenocarcinoma, and renal cell cancer.
renal collecting tubule: listen (REE-nul kuh-LEK-ting TOO-byool); 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: listen (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 renal 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: listen (REE-nul FA-shuh); A fibrous envelope of tissue that surrounds the kidney. Also called Gerota's capsule and Gerota's fascia.
renal function: listen (REE-nul FUNK-shun); A term used to describe how well the kidneys work. The kidneys remove waste and extra water from the blood (as urine) and help keep chemicals (such as sodium, potassium, and calcium) balanced in the body. They also make hormones that help control blood pressure and stimulate bone marrow to make red blood cells. Also called kidney function.
renal function test: listen (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: listen (REE-nul gloh-MAYR-yoo-lus); 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: listen (REE-nul PEL-vus); 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: listen (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.
renal tubule: listen (REE-nul TOO-byool); A small tube in the kidney that contains cells that filter and clean the blood. There are about 1 million renal tubules in each kidney. The renal tubules make urine by removing waste, extra fluid, and other substances from the blood. Urine moves through the renal tubules into the tubes that carry urine from the kidney to the bladder.
renal vein: listen (REE-nul vayn); The main blood vessel that carries blood from the kidney and ureter to the inferior vena cava (a large vein that carries blood to the heart from the lower part of the body). There is a renal vein for each kidney.
Renova: listen (ree-NOH-vuh); A topical preparation of tretinoin that is used to treat acne. Tretinoin is a form of vitamin A.
replicate: listen (REH-plih-kayt); To make a copy or duplicate of something.
replication cycle: listen (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.
R-EPOCH: An abbreviation for a chemotherapy combination used to treat certain types of non-Hodgkin lymphoma. It includes the drugs rituximab, etoposide phosphate, prednisone, vincristine sulfate (Oncovin), cyclophosphamide, and doxorubicin hydrochloride (hydroxydaunorubicin). Also called R-EPOCH regimen.
R-EPOCH regimen: listen (... REH-jih-men); An abbreviation for a chemotherapy combination used to treat certain types of non-Hodgkin lymphoma. It includes the drugs rituximab, etoposide phosphate, prednisone, vincristine sulfate (Oncovin), cyclophosphamide, and doxorubicin hydrochloride (hydroxydaunorubicin). Also called R-EPOCH.
reproductive cell: listen (REE-proh-DUK-tiv sel); An egg or sperm cell. Each mature reproductive cell carries a single set of 23 chromosomes.
reproductive endocrinologist: listen (REE-proh-DUK-tiv EN-doh-krih-NAH-loh-jist); A doctor who has special training in the diagnosis and treatment of infertility. A reproductive endocrinologist may use surgery, medicine, or procedures, such as in vitro fertilization (IVF), to treat infertility. A reproductive endocrinologist may also use procedures, such as sperm banking and egg freezing, to help keep a person’s ability to have children. This is called fertility preservation.
reproductive hormone: listen (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.
reproductive medicine: listen (REE-proh-DUK-tiv MEH-dih-sin); A branch of medicine that specializes in fertility preservation, diagnosing and treating infertility, and other reproductive problems. Reproductive medicine also deals with issues related to puberty, menopause, contraception (birth control), and certain sexual problems.
reproductive system: listen (REE-proh-DUK-tiv SIS-tem); The organs involved in producing offspring. In women, this system includes the ovaries, the fallopian tubes, the uterus, the cervix, and the vagina. In men, it includes the prostate, the testes, and the penis.
rescue transplant: listen (REH-skyoo TRANZ-plant); A method of replacing blood-forming stem cells that were destroyed by treatment with high doses of anticancer drugs or radiation therapy. The stem cells help the bone marrow recover and make healthy blood cells. A rescue transplant may allow more chemotherapy or radiation therapy to be given so that more cancer cells are killed. It is usually done using the patient’s own stem cells that were saved before treatment. Also called stem cell rescue.
research advocate: listen (REE-serch AD-vuh-kut); A person who serves as a link between patients and scientific researchers. Research advocates help patients understand scientific information and research findings that may help them. They may also bring a patient perspective on research activities to scientific advisory boards and committees. For example, research advocates use their own experiences and the experiences of patients to work with researchers to help develop clinical trials that are safe and meet the needs of patients. They also help teach patients and their families about clinical trials and recruit patients to clinical trials.
research base: listen (REE-serch bays); Refers to the institutions, clinical staff, and patients that can take part in a clinical trial.
research study: listen (REE-serch STUH-dee); 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.
resectable: listen (ree-SEK-tuh-bul); Able to be removed by surgery.
resected: listen (ree-SEK-ted); Removed by surgery.
resection: listen (ree-SEK-shun); Surgery to remove tissue or part or all of an organ.
resectoscope: listen (ree-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: listen (ree-ZID-yoo-ul dih-ZEEZ); Cancer cells that remain after attempts to remove the cancer have been made.
resin: listen (REH-zin); A thick substance that comes from plants or can be made in the laboratory from certain chemicals. Resins do not dissolve in water, and are used in plastics, varnishes, printing inks, medicine, and to make fabrics stiff.
resiquimod: listen (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: listen (reh-ZIH-stunt KAN-ser); 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: listen (ree-SORP-shun); A process in which a substance, such as tissue, is lost by being destroyed and then absorbed by the body.
respirator: listen (RES-pih-RAY-ter); In medicine, a machine used to help a patient breathe. Also called ventilator.
respiratory disease: listen (RES-pih-ruh-TOR-ee dih-ZEEZ); A type of disease that affects the lungs and other parts of the respiratory system. Respiratory diseases may be caused by infection, by smoking tobacco, or by breathing in secondhand tobacco smoke, radon, asbestos, or other forms of air pollution. Respiratory diseases include asthma, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, pneumonia, and lung cancer. Also called lung disorder and pulmonary disease.
respiratory syncytial virus: listen (RES-pih-ruh-TOR-ee sin-SIH-shul VY-rus); A virus that causes respiratory infections with cold-like symptoms. Also called RSV.
respiratory system: listen (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: listen (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: listen (RES-pih-ruh-TOR-ee THAYR-uh-pee); Exercises and treatments that help improve or restore lung function.
respiratory tract: listen (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.
respite care: listen (REH-spit kayr); Temporary care given to a person who is unable to care for himself or herself so that the usual caregivers can have a break. Respite care may include in-home care, adult daycare, or nursing home care.
response: listen (reh-SPONTS); In medicine, an improvement related to treatment.
Response Evaluation Criteria In Solid Tumors: listen (reh-SPONTS ee-VAL-yoo-AY-shun kry-TEER-ee-uh … SAH-lid TOO-mers); A standard way to measure how well a cancer patient responds to treatment. It is based on whether tumors shrink, stay the same, or get bigger. To use Response Evaluation Criteria In Solid Tumors, there must be at least one tumor that can be measured on x-rays, CT scans, or MRI scans. The types of response a patient can have are a complete response (CR), a partial response (PR), progressive disease (PD), and stable disease (SD). Also called RECIST.
response rate: listen (reh-SPONTS...); The percentage of patients whose cancer shrinks or disappears after treatment.
restaging: listen (ree-STAY-jing); A process used to find out the amount or spread of cancer in the body if it comes back or gets worse after treatment. Restaging may also be done to find out how the cancer responded to treatment. If restaging is done and a new stage is assigned, the new stage will be marked with an “r” in front of it to show that it’s different from the original stage. Usually, the original stage stays the same, even if the cancer comes back or gets worse. The same tests that were done to diagnose the cancer are usually done again. Restaging helps doctors plan the best treatment for cancer that has come back or gotten worse.
resting: listen (RES-ting); In biology, refers to a cell that is not dividing.
restless legs syndrome: listen (… SIN-drome); A condition in which a person has a strong urge to move his or her legs in order to stop uncomfortable sensations. These include burning, itching, creeping, tugging, crawling, or pain. These feelings usually happen when a person is lying or sitting down, and are worse at night. They can also occur in other parts of the body. Also called RLS.
resveratrol: listen (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.
Retacrit: listen (REH-tuh-krit); A drug used to treat anemia caused by chronic kidney disease, some types of chemotherapy, and an antiviral drug for HIV infection called zidovudine. It is also used to lower the number of donor blood transfusions needed during and after certain types of surgery. Retacrit is a form of erythropoietin (a substance naturally made by the kidneys) that is made in the laboratory. It helps the bone marrow make more red blood cells. Retacrit is a type of antianemic and a type of erythropoiesis-stimulating agent. Also called epoetin alfa, Epogen, and Procrit.
retch: listen (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.
rete testis: listen (REE-tee TES-tis); A network of small tubes in the testicle that helps move sperm cells (male reproductive cells) from the testicle to the epididymis. The epididymis is where the sperm mature and are stored.
reticular dermis: listen (reh-TIH-kyoo-ler DER-mis); The thick bottom layer of the dermis (the inner layer of the skin). The reticular dermis has blood vessels and connective tissue that supports the skin. Hair follicles, oil and sweat glands, and other structures are also found in the reticular dermis.
retiform hemangioendothelioma: listen (REE-tih-form hee-MAN-jee-oh-EN-doh-THEE-lee-OH-muh); A rare, slow-growing tumor that usually forms on or under the skin of the arms, legs, and trunk. The tumor has blood vessels that branch out like a tree. Retiform hemangioendotheliomas can spread to nearby tissue and often come back after treatment. They usually do not spread to other parts of the body. They occur in young adults and sometimes children. Retiform hemangioendotheliomas are a type of vascular tumor.
retina: listen (REH-tih-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.
Retin-A: listen (REH-tin …); A topical preparation of tretinoin that is used to treat acne. Tretinoin is a form of vitamin A.
Retin-A-Micro: listen (REH-tin … MY-kroh); A topical preparation of tretinoin that is used to treat acne. Tretinoin is a form of vitamin A.
retinoblastoma: listen (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: listen (REH-tih-NOH-ik A-sid); A nutrient that the body needs in small amounts to function and stay healthy. Retinoic acid is made in the body from vitamin A and helps cells to grow and develop, especially in the embryo. A form of retinoic acid made in the laboratory is put on the skin to treat conditions such as acne and is taken by mouth to treat acute promyelocytic leukemia (a fast-growing cancer in which there are too many immature blood-forming cells in the blood and bone marrow). Retinoic acid is being studied in the prevention and treatment of other types of cancer. Also called all-trans retinoic acid, ATRA, tretinoin, and vitamin A acid.
retinoic acid receptor alpha gene: listen (REH-tih-NOH-ik A-sid reh-SEP-ter AL-fuh jeen); A gene that makes a protein called retinoic acid receptor alpha (RARA), which controls the activity of certain genes that help white blood cells mature. Mutations (changes) in the retinoic acid receptor alpha gene can occur when a piece of the chromosome containing the retinoic acid receptor alpha gene breaks off and joins with a gene called PML on another chromosome. These changes may cause too many immature white blood cells to build up in the blood and bone marrow. This can lead to an aggressive (fast-growing) type of acute myeloid leukemia called acute promyelocytic leukemia. The protein made by the retinoic acid receptor alpha gene is a type of transcription factor. Also called RARA gene.
retinoid: listen (REH-tih-noyd); Vitamin A or a vitamin A-like compound.
retinol: listen (REH-tih-nol); A nutrient that the body needs in small amounts to function and stay healthy. Retinol helps in vision, bone growth, reproduction, growth of epithelium (cells that line the internal and external surfaces of the body), and fighting infections. It is fat-soluble (can dissolve in fats and oils). Retinol is found in liver, egg yolks, and whole milk dairy products from animals and in fish oils. It can also be made in the body from a substance found in some fruits and vegetables, such as cantaloupes, carrots, spinach, and sweet potatoes. Retinol is being studied in the prevention and treatment of some types of cancer. Also called vitamin A.
retinyl palmitate: listen (REH-tih-nil PAL-mih-tayt); A drug that is being studied in the prevention of cancer. It belongs to the family of drugs called retinoids.
retromolar trigone: listen (reh-troh-MOH-ler TRY-gone); The small area behind the wisdom teeth.
retroperitoneal: listen (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).
retroperitoneum: listen (REH-troh-PAYR-ih-toh-NEE-um); The area in the back of the abdomen behind the peritoneum (the tissue that lines the abdominal wall and covers most of the organs in the abdomen). The organs in the retroperitoneum include the adrenal glands, aorta, kidneys, esophagus, ureters, pancreas, rectum, and parts of the stomach and colon.
retropubic prostatectomy: listen (reh-troh-PYOO-bik PROS-tuh-TEK-toh-mee); Surgery to remove part or all of the prostate and some of the tissue around it. Nearby lymph nodes may also be removed. A retropubic prostatectomy may be done through an incision (cut) made in the wall of the lower abdomen, or it may be done using a laparoscope. A laparoscope is a thin, tube-like instrument with a light and lens for viewing. Several small incisions (cuts) are made in the wall of the abdomen, and the laparoscope is inserted through one opening to guide the surgery. Surgical instruments are inserted through the other openings to do the surgery.
retrospective: listen (REH-troh-SPEK-tiv); Looking back at events that have already taken place.
retrospective cohort study: listen (REH-troh-SPEK-tiv KOH-hort STUH-dee); 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 historic cohort study.
retrospective study: listen (REH-troh-SPEK-tiv STUH-dee); 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 case-control study.
retroviral vector: listen (REH-troh-VY-rul VEK-ter); RNA from a virus that is used to insert genetic material into cells.
retrovirus: listen (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.
reverse transcription: listen (ree-VERS tran-SKRIP-shun); In biology, the process in cells by which an enzyme makes a copy of DNA from RNA. The enzyme that makes the DNA copy is called reverse transcriptase and is found in retroviruses, such as the human immunodeficiency virus (HIV). Reverse transcription can also be carried out in the laboratory.
reverse transcription-polymerase chain reaction: listen (ree-VERS tran-SKRIP-shun-puh-LIH-meh-rays chayn ree-AK-shun); A laboratory method used to make many copies of a specific genetic sequence for analysis or other studies. It uses an enzyme called reverse transcriptase to change a specific piece of RNA into DNA, which can be amplified (made in large numbers) by another enzyme called DNA polymerase. Reverse transcription-polymerase chain reaction may be used to look for certain changes in a gene or chromosome, which may help diagnose a disease, such as cancer. It may also be used to study the RNA of certain viruses, such as the human immunodeficiency virus (HIV) and the hepatitis C virus, to help diagnose and monitor an infection. Also called RT-PCR.
reversible posterior leukoencephalopathy syndrome: listen (ree-VER-sih-bul pos-TEER-ee-er LOO-koh-en-SEH-fuh-LAH-puh-thee SIN-drome); A rare condition marked by headaches, vision problems, mental changes, seizures, and swelling in the brain. The symptoms of reversible posterior leukoencephalopathy syndrome usually come on quickly and can be serious and life threatening. When treated, symptoms often go away within days or weeks. Reversible posterior leukoencephalopathy syndrome may occur in patients with certain conditions, such as high blood pressure, eclampsia, severe infection, kidney disease, and certain autoimmune diseases. It may also occur in patients treated with certain anticancer drugs and immunosuppressive drugs. Also called posterior reversible encephalopathy syndrome, PRES, and RPLS.
ReVia: listen (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: listen (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 used to treat mantle cell lymphoma that has come back or has not gotten better after other treatment. It is being studied in the treatment of other conditions and types of cancer. Revlimid may help the immune system kill abnormal blood cells or cancer cells. It may also prevent the growth of new blood vessels that tumors need to grow. It is a type of antiangiogenesis agent and a type of immunomodulating agent. Also called CC-5013 and lenalidomide.
RevM10 gene: listen (… jeen); An antiviral gene that is being studied in the treatment of cancer in patients who have HIV, the virus that causes AIDS.
Reye syndrome: listen (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.
R-flurbiprofen: listen (… FLOOR-bih-PROH-fen); A substance that is being studied as a treatment for cancer. It belongs to the family of drugs called nonsteroidal anti-inflammatory drugs (NSAIDs).
RFS: In cancer, the length of time after primary treatment for a cancer ends that the patient survives without any signs or symptoms of that cancer. In a clinical trial, measuring the RFS is one way to see how well a new treatment works. Also called DFS, disease-free survival, and relapse-free survival.
RFT5-dgA immunotoxin: listen (... 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.
rF-TRICOM: listen; 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.
RG7204: A drug used to treat Erdheim-Chester disease (a very rare type of histiocytosis) and advanced melanoma. It is used in patients whose disease has a mutated (changed) form of a gene called BRAF. It is also being studied in the treatment of other types of cancer. RG7204 blocks certain proteins made by the mutated BRAF gene, which may help keep cancer cells from growing. It is a type of kinase inhibitor and a type of targeted therapy agent. Also called BRAF (V600E) kinase inhibitor RO5185426, PLX4032, vemurafenib, and Zelboraf.
rhabdoid tumor: listen (RAB-doyd TOO-mer); 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: listen (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: listen (ROO-muh-TIH-zum); 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: listen (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: listen (ROO-muh-trex); A drug used to treat many types of cancer. It is also used to treat rheumatoid arthritis and severe psoriasis (a type of skin condition). Rheumatrex stops cells from using folic acid to make DNA and may kill cancer cells. It may also lower the body’s immune response. Rheumatrex is a type of antimetabolite and a type of antifolate. Also called amethopterin, methotrexate, MTX, and Trexall.
rhIL-11: A drug used to increase the number of blood cells, especially platelets, in some cancer patients receiving chemotherapy. rhIL-11 is a form of interleukin-11 (a cytokine normally made by support cells in the bone marrow) that is made in the laboratory. It is a type of biological response modifier. Also called Neumega, oprelvekin, and recombinant human interleukin-11.
rhinoscope: listen (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 nasoscope.
rhinoscopy: listen (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: listen (ry-ZOK-sin); 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: listen (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 Chinese rhubarb, da-huang, Indian rhubarb, and Turkish rhubarb.
ribavirin: listen (RY-buh-VY-rin); A drug used to treat respiratory syncytial virus (RSV) infection in the lungs.
ribociclib succinate: listen (RY-boh-SY-klib SUK-sih-nayt); A drug used to treat hormone-receptor positive (HR+), HER2 negative (HER2-) breast cancer that is advanced or has spread to other parts of the body. It is used with an aromatase inhibitor (a type of hormone therapy) in women who have not been treated with hormone therapy. It is used with fulvestrant in postmenopausal women who have not been treated with hormone therapy or whose cancer got worse during treatment with hormone therapy. It is also being studied in the treatment of other types of cancer. Ribociclib succinate blocks certain proteins, which may help keep cancer cells from growing. It is a type of cyclin-dependent kinase inhibitor. Also called Kisqali.
riboflavin: listen (RY-boh-FLAY-vin); A nutrient in the vitamin B complex that the body needs in small amounts to function and stay healthy. Riboflavin helps make red blood cells, helps some enzymes work properly, and keeps skin, nails, and hair healthy. It is found in milk, eggs, malted barley, organ meats, yeast, and leafy vegetables. Riboflavin is water-soluble (can dissolve in water) and must be taken in every day. Not enough riboflavin can cause anemia (a low number of red blood cells), mouth sores, and skin problems. Amounts of riboflavin may be higher in the blood of patients with some types of cancer. Also called vitamin B2.
ribonucleic acid: listen (RY-boh-noo-KLAY-ik A-sid); One of two types of nucleic acid made by cells. Ribonucleic acid contains information that has been copied from DNA (the other type of nucleic acid). Cells make several different forms of ribonucleic acid, and each form has a specific job in the cell. Many forms of ribonucleic acid have functions related to making proteins. Ribonucleic acid is also the genetic material of some viruses instead of DNA. Ribonucleic acid can be made in the laboratory and used in research studies. Also called RNA.
ribonucleotide reductase inhibitor: listen (RY-boh-NOO-klee-oh-tide ree-DUK-tays in-HIH-bih-ter); A family of anticancer drugs that interfere with the growth of tumor cells by blocking the formation of deoxyribonucleotides (building blocks of DNA).
ribosome: listen (RY-buh-some); In biology, a structure found inside cells that is involved in making proteins. Ribosomes help link amino acids together to form proteins.
R-ICE: An abbreviation for a chemotherapy combination used to treat certain types of non-Hodgkin lymphoma. It includes the drugs rituximab, ifosfamide, carboplatin, and etoposide phosphate. Also called R-ICE regimen.
R-ICE regimen: listen (… REH-jih-men); An abbreviation for a chemotherapy combination used to treat certain types of non-Hodgkin lymphoma. It includes the drugs rituximab, ifosfamide, carboplatin, and etoposide phosphate. Also called R-ICE.
Richter syndrome: listen (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: listen (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.
rickets: listen (RIH-kets); A condition in children in which bones become soft and deformed because they don’t have enough calcium and phosphorus. It is caused by not having enough vitamin D in the diet or by not getting enough sunlight. In adults, this condition is called osteomalacia. Also called infantile rickets, juvenile rickets, and rachitis.
ridaforolimus: listen (rih-duh-foh-ROH-lih-mus); A substance being studied in the treatment of soft tissue and bone cancers. It is also being studied in the treatment of other solid tumors and hematologic cancer. Ridaforolimus stops cells from dividing and may cause cancer cells to die. It is a type of mTOR inhibitor. Also called AP23573.
rifabutin: listen (RIH-fuh-BYOO-tin); A drug used to prevent the spread of a bacterium called in patients with advanced HIV (the virus that causes AIDS) infection. It blocks an enzyme that the bacteria need to grow. It is a type of antibiotic. Also called Mycobutin.
rifampin: listen (rih-FAM-pin); A drug used in the treatment of infections caused by bacteria. It belongs to the family of drugs called antibiotics.
Rilutek: listen (RIL-yoo-tek); A drug used to treat a nerve disease called amyotrophic lateral sclerosis (ALS). It is also being studied in the treatment of melanoma (a type of skin cancer). Rilutek blocks the release of a substance that melanoma cells need to grow. It is a type of glutamate release inhibitor. Also called riluzole.
riluzole: listen (RIL-yoo-zole); A drug used to treat a nerve disease called amyotrophic lateral sclerosis (ALS). It is also being studied in the treatment of melanoma (a type of skin cancer). Riluzole blocks the release of a substance that melanoma cells need to grow. It is a type of glutamate release inhibitor. Also called Rilutek.
risedronate: listen (rih-SEH-droh-nayt); 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 assessment: listen (… uh-SES-ment); A process used to estimate the risk that a certain event will happen. In medicine, this may include a person’s risk of having a child with a certain condition or disease, such as cancer. It may also be used to estimate the risk of carrying a certain gene mutation (change), or of having an adverse event (unexpected medical problem) in response to certain types of drugs or other substances. A risk assessment may be done by collecting information about a person’s age, sex, personal and family medical history, ethnic background, lifestyle, and other factors and using statistics tools to calculate risk.
risk factor: listen (... FAK-ter); Something that increases the chance of developing a disease. Some examples of risk factors for cancer are age, a family history of certain cancers, use of tobacco products, being exposed to radiation or certain chemicals, infection with certain viruses or bacteria, and certain genetic changes.
risk group: listen (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.
risk ratio: listen (… RAY-shee-oh); A measure of the risk of a certain event happening in one group compared to the risk of the same event happening in another group. In cancer research, risk ratios are used in prospective (forward looking) studies, such as cohort studies and clinical trials. A risk ratio of one means there is no difference between two groups in terms of their risk of cancer, based on whether or not they were exposed to a certain substance or factor, or how they responded to two treatments being compared. A risk ratio of greater than one or of less than one usually means that being exposed to a certain substance or factor either increases (risk ratio greater than one) or decreases (risk ratio less than one) the risk of cancer, or that the treatments being compared do not have the same effects. Also called relative risk.
Risperdal: listen (RIS-per-dal); A drug used to treat certain mental disorders, such as schizophrenia and bipolar disease. It may also be used to treat certain behavior problems in children. Risperdal blocks the action of certain chemicals in the brain. It is a type of antipsychotic. Also called risperidone.
risperidone: listen (ris-PAYR-ih-done); A drug used to treat certain mental disorders, such as schizophrenia and bipolar disease. It may also be used to treat certain behavior problems in children. Risperidone blocks the action of certain chemicals in the brain. It is a type of antipsychotic. Also called Risperdal.
Ritalin: listen (RIH-tuh-lin); A drug used to treat certain behavior disorders, such as attention deficit hyperactivity disorder (ADHD). It is also being studied as a way to improve brain function in patients treated with anticancer drugs. Ritalin acts on certain parts of the brain. It is a type of central nervous system stimulant. Also called Concerta and methylphenidate hydrochloride.
ritonavir: listen (ry-TOH-nuh-veer); A drug used to treat infection with HIV (the virus that causes AIDS). It is also being studied in the treatment of some types of cancer. Ritonavir blocks the ability of HIV to make copies of itself and may block the growth of cancer cells. It is a type of anti-HIV agent and a type of protease inhibitor. Also called Norvir.
ritual: listen (RIH-chuh-wul); An action or series of actions that is repeated, often in a religious or social setting. In medicine, it may describe a repeated action (such as hand washing) done to relieve feelings of fear, dread, and uneasiness in people who have an obsessive-compulsive disorder.
Rituxan: listen (rih-TUK-sun); A drug used alone or with other drugs to treat certain types of chronic lymphocytic leukemia and B-cell non-Hodgkin lymphoma that are CD20 positive. It is also being studied in the treatment of other conditions and types of cancer. Rituxan 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. Rituxan contains the active ingredient rituximab. It is a type of monoclonal antibody.
Rituxan Hycela: listen (rih-TUK-sun hy-SEL-uh); A combination of two drugs used to treat certain types of follicular lymphoma, diffuse large B-cell lymphoma, and chronic lymphocytic leukemia. It is a combination of rituximab and hyaluronidase. Rituximab binds to a protein called CD20, which is found on B cells (a type of white blood cell) and some types of cancer cells. This may help the immune system kill cancer cells. Hyaluronidase allows rituximab to be given by injection under the skin. Giving Rituxan Hycela by injection is faster than giving rituximab alone by infusion. Also called rituximab and hyaluronidase.
rituximab: listen (rih-TUK-sih-mab); 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.
rituximab and hyaluronidase: listen (rih-TUK-sih-mab … HY-al-yoo-RAH-nih-days); A combination of two drugs used to treat certain types of follicular lymphoma, diffuse large B-cell lymphoma, and chronic lymphocytic leukemia. It is a combination of rituximab and hyaluronidase. Rituximab binds to a protein called CD20, which is found on B cells (a type of white blood cell) and some types of cancer cells. This may help the immune system kill cancer cells. Hyaluronidase allows rituximab to be given by injection under the skin. Giving rituximab and hyaluronidase by injection is faster than giving rituximab alone by infusion. Also called Rituxan Hycela.
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.
RLS: A condition in which a person has a strong urge to move his or her legs in order to stop uncomfortable sensations. These include burning, itching, creeping, tugging, crawling, or pain. These feelings usually happen when a person is lying or sitting down, and are worse at night. They can also occur in other parts of the body. Also called restless legs syndrome.
r-metHuSCF: A substance that causes blood stem cells (cells from which other types of cells develop) to change into different types of blood cells and increases the number and actions of these cells in the blood. It is being studied in the treatment of myelodysplasia. r-metHuSCF is a type of recombinant stem cell growth factor. Also called ancestim, recombinant human methionyl stem cell factor, and Stemgen.
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: One of two types of nucleic acid made by cells. RNA contains information that has been copied from DNA (the other type of nucleic acid). Cells make several different forms of RNA, and each form has a specific job in the cell. Many forms of RNA have functions related to making proteins. RNA is also the genetic material of some viruses instead of DNA. RNA can be made in the laboratory and used in research studies. 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.
RO4929097: A substance being studied in the treatment of cancer. It blocks certain enzymes that are needed for cell growth. This may slow the growth of cancer cells. It may also decrease the growth of new blood vessels that tumors need to grow. It is a type of gamma-secretase inhibitor and a type of Notch signaling inhibitor.
rofecoxib: listen (ROH-feh-KOK-sib); A drug that was being used for pain relief and was being studied for its ability to prevent cancer and to prevent the growth of new blood vessels that tumors need to grow. It is a type of nonsteroidal anti-inflammatory drug and a type of antiangiogenesis agent. Rofecoxib was taken off the market in the U.S. because of safety concerns. Also called Vioxx.
rolapitant hydrochloride: listen (roh-LA-pih-tunt HY-droh-KLOR-ide); A drug used with other drugs to prevent nausea and vomiting caused by chemotherapy. Rolapitant hydrochloride blocks the action of chemicals in the central nervous system (CNS) that may trigger nausea and vomiting. It is a type of antiemetic. Also called Varubi.
Roman chamomile: listen (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: listen (ROH-mih-DEP-sin); A drug used to treat cutaneous T-cell lymphoma and peripheral T-cell lymphoma that have already been treated with other anticancer drugs. It is also being studied in the treatment of other types of cancer. Romidepsin blocks certain enzymes, which may help kill cancer cells. It is a type of depsipeptide and a type of histone deacetylase inhibitor. Also called FR901228 and Istodax.
romiplostim: listen (ROH-mih-PLOH-stim); A drug used to treat thrombocytopenia (low platelet levels) in patients with immune thrombocytopenic purpura (ITP) that did not get better with other treatment. ITP is a condition in which platelets are destroyed by the immune system. Romiplostim binds to the thrombopoietin receptor, which causes the bone marrow to make more platelets. It is a type of thrombopoietin receptor agonist. Also called AMG 531 and Nplate.
ropivacaine: listen (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 Naropin and ropivacaine hydrochloride.
ropivacaine hydrochloride: listen (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 Naropin and ropivacaine.
ROS1 gene: listen (… jeen); A gene that makes a protein called ROS1, which is involved in sending signals in cells and in cell growth. Mutated (changed) forms of the ROS1 gene have been found in some types of cancer, including non-small cell lung cancer (NSCLC), a type of brain cancer called glioblastoma multiforme, and cancers of the bile duct, ovary, stomach, colon, and rectum. ROS1 is a type of receptor tyrosine kinase.
rosiglitazone: listen (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 prevent 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: listen (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 prevent 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.
rosuvastatin calcium: listen (roh-SOO-vuh-STA-tin KAL-see-um); A drug used to lower the amount of cholesterol and other harmful substances, such as triglycerides, in the blood. It is also being studied in the prevention and treatment of some types of cancer and other conditions. Rosuvastatin calcium blocks an enzyme that helps make cholesterol in the body and it helps break down cholesterol. It also may cause cancer cells to die and may inhibit the growth of blood vessels that cancer cells need to grow. It is a type of HMG-CoA reductase inhibitor and a type of statin. Also called Crestor.
Roswell Park regimen: listen (ROZ-wel … REH-jih-men); A chemotherapy combination used to treat colorectal cancer. It is also used with radiation therapy to treat esophageal cancer and stomach cancer. It includes the drugs fluorouracil and leucovorin calcium.
rotationplasty: listen (roh-TAY-shun-PLAS-tee); Surgery used to remove a tumor in or near the knee joint, often in young people who are still growing. The knee and part of the thigh are removed. The part of the leg that remains below the knee is then attached to the part of the leg above the knee, with the foot facing backward and the ankle joint acting as a new knee. The patient is then fitted with an artificial lower leg and foot.
Rothmund-Thomson syndrome: listen (ROT-moond-TOM-sun SIN-drome); A rare inherited disorder that affects the skin and many other parts of the body, including the bones, eyes, nose, hair, nails, teeth, testes, and ovaries. People with Rothmund-Thomson syndrome have an increased risk of osteosarcoma (bone cancer). Also called RTS.
RPI.4610: A substance being studied in the treatment of cancer. RPI.4610 is a special type of RNA made in the laboratory. It stops a protein called vascular endothelial growth factor receptor (VEGFR) from being made. This may prevent the growth of new blood vessels that tumors need to grow. It is a type of angiogenesis inhibitor and a type of ribozyme. Also called Angiozyme.
RPLS: A rare condition marked by headaches, vision problems, mental changes, seizures, and swelling in the brain. The symptoms of RPLS usually come on quickly and can be serious and life threatening. When treated, symptoms often go away within days or weeks. RPLS may occur in patients with certain conditions, such as high blood pressure, eclampsia, severe infection, kidney disease, and certain autoimmune diseases. It may also occur in patients treated with certain anticancer drugs and immunosuppressive drugs. Also called posterior reversible encephalopathy syndrome, PRES, and reversible posterior leukoencephalopathy syndrome.
RPR 109881A: A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called taxanes.
RRP: A rare condition in which wart-like growths called papillomas grow in the respiratory tract (air passages leading from the nose and mouth into the lungs). The papillomas most often grow in the larynx (voice box) and vocal cords. They can grow quickly, and they often grow back after they have been removed by surgery. Signs and symptoms of RRP include hoarseness, chronic cough, swallowing problems, and breathing problems, which may sometimes be life-threatening. RRP is caused by infection with certain types of human papillomavirus (HPV). It can occur in both children and adults. Also called recurrent respiratory papillomatosis.
RSR13: A substance being studied in the treatment of brain tumors and some other types of cancer. It increases the amount of oxygen in tumor tissues, which may make the tumor cells easier to kill with radiation therapy. RSR13 is a type of radiosensitizing agent. Also called efaproxiral.
RSV: 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. It is a type of topoisomerase inhibitor. Also called topoisomerase II inhibitor RTA 744.
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 Activase, Alteplase, and recombinant tissue plasminogen activator.
RT-PCR: A laboratory method used to make many copies of a specific genetic sequence for analysis or other studies. It uses an enzyme called reverse transcriptase to change a specific piece of RNA into DNA, which can be amplified (made in large numbers) by another enzyme called DNA polymerase. RT-PCR may be used to look for certain changes in a gene or chromosome, which may help diagnose a disease, such as cancer. It may also be used to study the RNA of certain viruses, such as the human immunodeficiency virus (HIV) and the hepatitis C virus, to help diagnose and monitor an infection. Also called reverse transcription-polymerase chain reaction.
RTS: A rare inherited disorder that affects the skin and many other parts of the body, including the bones, eyes, nose, hair, nails, teeth, testes, and ovaries. People with RTS have an increased risk of osteosarcoma (bone cancer). Also called Rothmund-Thomson syndrome.
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 Mifeprex and mifepristone.
Rubinstein-Taybi syndrome: listen (ROO-bin-stine-TAY-bee SIN-drome); A rare, genetic disorder marked by being short, having wide big toes and thumbs, certain facial features, and problems in developing and learning. Other problems may include heart and kidney defects, eye and dental problems, and obesity. People with Rubinstein syndrome have an increased risk of some types of leukemia and brain tumors.
Rubraca: listen (roo-BRAH-kuh); A drug used to treat recurrent ovarian epithelial, fallopian tube, or primary peritoneal cancer that has gotten better after treatment with anticancer drugs that included platinum. It is used to help keep the cancer from coming back again. Rubraca is also used in patients whose cancer has certain mutations (changes) in the BRCA1 or BRCA2 genes and who have already been treated with at least two other types of anticancer drugs. It is also being studied in the treatment of other types of cancer. Rubraca blocks an enzyme involved in many cell functions, including the repair of DNA damage. Blocking this enzyme may help keep cancer cells from growing and may kill them. Rubraca is a type of poly (ADP-ribose) polymerase inhibitor. Also called AG014699, PARP-1 inhibitor AG014699, and rucaparib camsylate.
rucaparib camsylate: listen (roo-KA-puh-rib KAM-suh-layt); A drug used to treat recurrent ovarian epithelial, fallopian tube, or primary peritoneal cancer that has gotten better after treatment with anticancer drugs that included platinum. It is used to help keep the cancer from coming back again. Rucaparib camsylate is also used in patients whose cancer has certain mutations (changes) in the BRCA1 or BRCA2 genes and who have already been treated with at least two other types of anticancer drugs. It is also being studied in the treatment of other types of cancer. Rucaparib camsylate blocks an enzyme involved in many cell functions, including the repair of DNA damage. Blocking this enzyme may help keep cancer cells from growing and may kill them. Rucaparib camsylate is a type of poly (ADP-ribose) polymerase inhibitor. Also called AG014699, PARP-1 inhibitor AG014699, and Rubraca.
ruxolitinib phosphate: listen (RUK-soh-LIH-tih-nib FOS-fayt); A drug used to treat polycythemia vera in patients who cannot be treated with or have not gotten better with hydroxyurea. It is also used to treat certain types of myelofibrosis. It is being studied in the treatment of other blood diseases and some types of cancer. Ruxolitinib phosphate blocks a protein called JAK, which may help keep abnormal blood cells or cancer cells from growing. It is a type of tyrosine kinase inhibitor. Also called Jakafi.
rV-TRICOM: listen; 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 recombinant vaccinia-TRICOM vaccine and vaccinia-TRICOM vaccine.
Rydapt: listen (RY-dapt); A drug used with cytarabine and daunorubicin to treat acute myeloid leukemia (AML) that has a mutated (changed) form of a gene called FLT3. It is also used to treat mast cell leukemia (a very rare type of leukemia) and systemic mastocytosis (a rare condition in which there are too many mast cells in the body). It is also being studied in the treatment of other types of cancer. Rydapt blocks certain proteins, which may help keep cancer cells from growing and may kill them. It may also prevent the growth of new blood vessels that tumors need to grow. Rydapt is a type of protein kinase inhibitor and a type of antiangiogenesis agent. Also called midostaurin, N-benzoyl-staurosporine, and PKC412.