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269 results found for:       D



D&C;   
A procedure to remove tissue from the cervical canal or the inner lining of the uterus. The cervix is dilated (made larger) and a curette (spoon-shaped instrument) is inserted into the uterus to remove tissue. Also called dilatation and curettage and dilation and curettage.

D-1MT   
A substance being studied in the treatment of melanoma and many other types of cancer. D-1MT blocks the breakdown of the amino acid tryptophan, which is needed for T cells (a type of immune system cell) to kill tumor cells. Giving D-1MT to patients who have received chemotherapy for cancer may help kill more tumor cells. It is a type of enzyme inhibitor and immunosuppressant. Also called 1-methyl-d-tryptophan.

D-20761   
A synthetic luteinizing hormone-releasing hormone (LH-RH) antagonist that suppresses LH and sex steroid levels.

D-cycloserine    (...SY-kloh-SER-een)
A drug used to treat tuberculosis. It is also being studied in the treatment of pain and nerve problems (numbness, tingling) caused by chemotherapy and in the treatment of low back pain, autism, certain anxiety disorders, and schizophrenia. D-cycloserine is a type of antibiotic. Also called Seromycin.

da-huang    (dah-hwong)
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, Indian rhubarb, rhubarb, and Turkish rhubarb.

DACA   
A substance being studied in the treatment of cancer. It is a type of topoisomerase inhibitor. Also called acridine carboxamide.

dacarbazine    (duh-KAR-buh-zeen)
A drug that is used to treat Hodgkin lymphoma and malignant melanoma and is being studied in the treatment of other types of cancer. It attaches to DNA in cells and may kill cancer cells. It is a type of alkylating agent. Also called DTIC-Dome.

dacliximab   
A monoclonal antibody that is being studied in the treatment of adult T-cell leukemia and in the treatment of cytopenia (low blood cell count). Also called daclizumab.

daclizumab   
A monoclonal antibody that is being studied in the treatment of adult T-cell leukemia and in the treatment of cytopenia (low blood cell count). Also called dacliximab.

Dacogen    (DA-koh-jen)
A drug that is used to treat myelodysplastic syndromes and is being studied in the treatment of other types of cancer. It is a type of antimetabolite. Also called decitabine.

dactinomycin   
An anticancer drug that is a type of antitumor antibiotic.

daidzein   
An isoflavone found in soy products. Soy isoflavones are being studied in the prevention of cancer.

dalteparin    (dul-TEP-uh-rin)
A drug used to prevent blood clots from forming or to treat blood clots that have formed in patients with cancer or other conditions. Dalteparin is a type of anticoagulant. Also called dalteparin sodium and Fragmin.

dalteparin sodium    (dul-TEP-uh-rin SOH-dee-um)
A drug used to prevent blood clots from forming or to treat blood clots that have formed in patients with cancer or other conditions. Dalteparin sodium is a type of anticoagulant. Also called dalteparin and Fragmin.

danazol   
A synthetic hormone that is a type of androgen and is used to treat endometriosis. It is being evaluated in the treatment of endometrial cancer.

daptomycin    (dap-toh-MY-sin)
A drug used to treat certain bacterial skin and bloodstream infections in adults. Daptomycin is also being studied in the treatment of fever and neutropenia (an abnormal decrease in the number of neutrophils, a type of white blood cell) in patients with cancer. It is a type of antibiotic. Also called Cubicin.

DAR   
A log of study drugs kept by an investigator running a clinical trial. It lists many things about each drug, including the drug name, lot number, expiration date, the amount of drug received, used, returned, or thrown away, and the amount left. DARs help make sure that a clinical trial is done safely and correctly. DARs are required by the U.S. Food and Drug Administration (FDA). Also called Drug Accountability Record.

darbepoetin alfa    (DAR-boh-poh-EE-tin AL-fuh)
A substance made in the laboratory that stimulates the bone marrow to produce red blood cells. It belongs to the family of drugs called antianemics.

dark-field microscope   
A microscope (device used to magnify small objects) in which objects are lit at a very low angle from the side so that the background appears dark and the objects show up against this dark background.

dasatinib    (da-SA-tih-nib)
A drug used to treat certain types of chronic myeloid leukemia and acute lymphoblastic leukemia. Dasatinib is also being studied in the treatment of certain other blood diseases and types of cancer. Dasatinib binds to and blocks BCR-ABL and other proteins that help cancer cells grow. It is a type of tyrosine kinase inhibitor. Also called BMS-354825 and Sprycel.

Data and Safety Monitoring Board   
An impartial group that oversees a clinical trial and reviews the results to see if they are acceptable. This group determines if the trial should be changed or closed. Also called DSMB.

daunomycin    (DAW-noh-MY-sin)
The active ingredient in a drug used to treat acute leukemias and some other types of cancer. It blocks a certain enzyme needed for cell division and DNA repair, and it may kill cancer cells. It is a type of anthracycline antibiotic and a type of topoisomerase inhibitor. Also called daunorubicin.

daunomycin hydrochloride    (DAW-noh-MY-sin HY-droh-KLOR-ide)
A drug used to treat acute leukemias and some other types of cancer. It blocks a certain enzyme needed for cell division and DNA repair, and it may kill cancer cells. Daunomycin hydrochloride is a type of anthracycline antibiotic and a type of topoisomerase inhibitor. Also called Cerubidine and daunorubicin hydrochloride.

daunorubicin    (DAW-noh-ROO-bih-sin)
The active ingredient in a drug used to treat acute leukemias and some other types of cancer. It blocks a certain enzyme needed for cell division and DNA repair, and it may kill cancer cells. It is a type of anthracycline antibiotic and a type of topoisomerase inhibitor. Also called daunomycin.

daunorubicin hydrochloride    (DAW-noh-ROO-bih-sin HY-droh-KLOR-ide)
A drug used to treat acute leukemias and some other types of cancer. It blocks a certain enzyme needed for cell division and DNA repair, and it may kill cancer cells. Daunorubicin hydrochloride is a type of anthracycline antibiotic and a type of topoisomerase inhibitor. Also called Cerubidine and daunomycin hydrochloride.

DCIS   
A noninvasive condition in which abnormal cells are found in the lining of a breast duct. The abnormal cells have not spread outside the duct to other tissues in the breast. In some cases, DCIS may become invasive cancer and spread to other tissues, although it is not known at this time how to predict which lesions will become invasive. Also called ductal carcinoma in situ and intraductal carcinoma.

DDS   
A rare disorder that causes kidney failure before age 3, abnormal development of the sexual organs, and, in most cases, Wilms tumor (a type of kidney cancer). Children with Denys-Drash syndrome are also at high risk of some other types of cancer. Also called Denys-Drash syndrome.

de novo    (dih NO-vo)
In cancer, the first occurrence of cancer in the body.

de qi sensation    (duh-CHEE sen-SAY-shun)
Tingling, numbness, heaviness, and other feelings that occur after an acupuncture needle has been properly placed in the body. The needle may be twirled, moved up and down at different speeds and depths, heated, or charged with a small electric current until the de qi sensation occurs.

death cap   
A type of poisonous mushroom that has harmful effects on the kidneys and liver. It is responsible for most fatal cases of mushroom poisoning. Also called Amanita phalloides.

death rattle    (... RA-tul)
A gurgling sound that comes from the back of the throat of a dying person. It is caused by the build-up of saliva and mucus in the throat and upper airways when the person is too weak to cough.

death receptor 4    (… reh-SEP-ter 4)
A protein on the surface of certain cells that binds another protein called TRAIL, which may kill some cancer cells. An increase in the amount or activity of death receptor 4 on cancer cells may kill more cells. Also called DR4, TRAIL receptor 1, TRAIL-R1, and tumor necrosis factor receptor superfamily member 10A.

death receptor 5    (… reh-SEP-ter 5)
A protein on the surface of certain cells that binds another protein called TRAIL, which may kill some cancer cells. An increase in the amount or activity of death receptor 5 on cancer cells may kill more cells. Also called DR5, TRAIL receptor 2, TRAIL-R2, and tumor necrosis factor receptor superfamily member 10B.

debulking    (dee-BUL-king)
Surgical removal of as much of a tumor as possible. Debulking may increase the chance that chemotherapy or radiation therapy will kill all the tumor cells. It may also be done to relieve symptoms or help the patient live longer. Also called tumor debulking.

deceased    (dih-SEEST)
Dead.

decitabine    (deh-SIT-uh-been)
A drug that is used to treat myelodysplastic syndromes and is being studied in the treatment of other types of cancer. It is a type of antimetabolite. Also called Dacogen.

declopramide    (deh-KLOH-pruh-mide)
A substance that blocks the process cells use to repair DNA. It may help anticancer drugs and radiation kill more cancer cells. It is a type of chemosensitizer and a type of radiosensitizer. Also called 3-chloroprocainamide and OXi-104.

decortication    (de-KOR-tih-KAY-shun)
Removal of part or all of the external surface of an organ.

deep vein thrombosis    (… vayn throm-BOH-sis)
The formation of a blood clot in a deep vein of the leg or lower pelvis. Symptoms may include pain, swelling, warmth, and redness in the affected area. Also called DVT.

defecation    (DEH-feh-kay-shun)
Movement of feces (undigested food, bacteria, mucus, and cells from the lining of the intestines) through the bowel and out the anus. Also called bowel movement.

deferasirox    (deh-FER-uh-SEER-ox)
A drug used to treat too much iron in the blood caused by blood transfusions. It is being studied in the treatment of myelodysplastic syndromes (a group of diseases in which the bone marrow does not make enough healthy blood cells) and other conditions. Deferasirox binds to extra iron in the blood. The drug and the iron are passed from the body in urine. It is a type of chelating agent. Also called Exjade.

deferoxamine   
An iron-chelating agent that removes iron from tumors by inhibiting DNA synthesis and causing cancer cell death. It is used in conjunction with other anticancer agents in pediatric neuroblastoma therapy.

defibrotide   
A substance that is being studied in the prevention of veno-occlusive disease, a rare complication of high-dose chemotherapy and stem cell transplantation in which small veins in the liver become blocked.

deficiency    (dih-FIH-shun-see)
In medicine, a shortage of a substance (such as a vitamin or mineral) needed by the body.

definitive treatment    (deh-FIH-nih-tiv TREET-ment)
The treatment plan for a disease or disorder that has been chosen as the best one for a patient after all other choices have been considered.

deforolimus    (deh-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. Deforolimus stops cells from dividing and may cause cancer cells to die. It is a type of mTOR inhibitor. Also called AP23573.

degarelix    (DEH-guh-REL-ix)
A drug that is used to treat advanced prostate cancer and is also being studied in the treatment of benign prostatic hyperplasia. Degarelix binds to gonadotropin-releasing hormone (GnRH) receptors in the pituitary gland. This causes the body to stop making testosterone, which prostate cancer needs to grow. Degarelix is a type of GnRH antagonist.

degenerative disease    (dih-JEH-neh-ruh-tiv dih-ZEEZ)
A disease in which the function or structure of the affected tissues or organs changes for the worse over time. Osteoarthritis, osteoporosis, and Alzheimer disease are examples.

dehydration   
A condition caused by the loss of too much water from the body. Severe diarrhea or vomiting can cause dehydration.

dehydroepiandrosterone   
A substance being studied in the prevention of cancer. It is a type of steroid. Also called DHEA.

delayed-type hypersensitivity response    (...HY-per-SEN-sih-TIH-vih-tee reh-SPONTS)
An inflammatory response that develops 24 to 72 hours after exposure to an antigen that the immune system recognizes as foreign. This type of immune response involves mainly T cells rather than antibodies (which are made by B cells). Also called DTH.

delirium    (deh-LEER-ee-um)
A mental state in which a person is confused, disoriented, and not able to think or remember clearly. The person may also be agitated and have hallucinations, and extreme excitement.

dementia    (deh-MEN-shuh)
A condition in which a person loses the ability to think, remember, learn, make decisions, and solve problems. Symptoms may also include personality changes and emotional problems. There are many causes of dementia, including Alzheimer disease, brain cancer, and brain injury. Dementia usually gets worse over time.

Demerol    (DEH-meh-ROL)
A drug used to treat moderate to severe pain. It binds to opioid receptors in the central nervous system. Demerol is a type of analgesic agent and a type of opioid. Also called meperidine hydrochloride.

dendritic cell   
A special type of immune cell that is found in tissues, such as the skin, and boosts immune responses by showing antigens on its surface to other cells of the immune system. A dendritic cell is a type of phagocyte and a type of antigen-presenting cell (APC).

dendritic cell vaccine   
A vaccine made of antigens and dendritic antigen-presenting cells (APCs).

denial    (deh-NY-ul)
In psychiatry, a state in which a person is unable or unwilling to see the truth or reality about an issue or situation.

denileukin diftitox    (DEN-ih-LOO-kin DIF-tih-tox)
A drug used to treat cutaneous T-cell lymphoma that can bind the cytokine IL-2 and that has not responded to other treatment. It is also being studied in the treatment of other types of cancer. Denileukin diftitox is made by combining a part of IL-2 with a bacterial toxin. The IL-2 part of the drug attaches to the cancer cells and then the toxin kills the cells. Denileukin diftitox is a type of immunotoxin and a type of fusion toxin. Also called Ontak.

denomination    (deh-NAH-mih-NAY-shun)
In religion, describes a group whose members are organized under a common name and set of rules and have common beliefs and practices.

denosumab    (den-oh-SOO-mab)
A type of monoclonal antibody being studied in the treatment of multiple myeloma (a cancer that forms in bones) and in the prevention and treatment of bone metastases (cancer that has spread to bone from another organ). Monoclonal antibodies are made in the laboratory and can locate and bind to substances in the body, including cancer cells. Denosumab binds to the protein RANKL and helps keep bone from breaking down. Also called AMG 162.

dental implant   
A metal device that is surgically placed in the jawbone. It acts as an anchor for an artificial tooth or teeth.

dentist   
A health professional who specializes in caring for the teeth, gums, and other tissues in the mouth.

Denys-Drash syndrome   
A rare disorder that causes kidney failure before age 3, abnormal development of the sexual organs, and, in most cases, Wilms tumor (a type of kidney cancer). Children with Denys-Drash syndrome are also at high risk of some other types of cancer. Also called DDS.

deoxycytidine   
A drug that protects healthy tissues from the toxic effects of anticancer drugs.

deoxyribonucleic acid    (dee-OK-see-RY-boh-noo-KLAY-ik A-sid)
The molecules inside cells that carry genetic information and pass it from one generation to the next. Also called DNA.

Depo-Cyt    (DEE-poh-SITE)
A form of the anticancer drug cytarabine that is contained inside very tiny, fat-like particles. It may have fewer side effects and work better than cytarabine. It is used to treat lymphoma that has spread to the meninges (three thin layers of tissue that cover and protect the brain and spinal cord). It is also being studied in the treatment of other types of cancer. It is a type of antimetabolite. Also called cytarabine liposome and liposomal cytarabine.

depression    (dee-PREH-shun)
A mental condition marked by ongoing feelings of sadness, despair, loss of energy, and difficulty dealing with normal daily life. Other symptoms of depression include feelings of worthlessness and hopelessness, loss of pleasure in activities, changes in eating or sleeping habits, and thoughts of death or suicide. Depression can affect anyone, and can be successfully treated. Depression affects 15-25% of cancer patients.

depsipeptide   
A substance that is made naturally by some bacteria, fungi, and other organisms, and can also be made in the laboratory. Depsipeptides are being studied in the treatment of cancer.

derivative   
In chemistry, a compound produced from or related to another.

dermabrasion    (DER-muh-BRAY-shun)
A type of surgery used to make the skin smooth and to improve the way deep scars, pits, and wrinkles look. After numbing the skin, a doctor removes the top layer of skin using sandpaper or a brush or burr (small file) that spins at a high speed.

dermatitis    (DER-muh-TY-tis)
Inflammation of the skin.

dermatofibrosarcoma protuberans    (DER-ma-toe-FI-bro-sar-KO-ma pro-TOO-ber-anz)
A type of tumor that begins as a hard nodule and grows slowly. These tumors are usually found in the dermis (the inner layer of the two main layers of tissue that make up the skin) of the limbs or trunk of the body. They can grow into surrounding tissue but do not spread to other parts of the body. These tumors are related to giant cell fibroblastomas.

dermatologist    (der-muh-TAH-loh-jist)
A doctor who has special training to diagnose and treat skin problems.

dermis    (DER-mis)
The inner layer of the two main layers of the skin. The dermis has connective tissue, blood vessels, oil and sweat glands, nerves, hair follicles, and other structures. It is made up of a thin upper layer called the papillary dermis, and a thick lower layer called the reticular dermis.

dermoid cyst    (DER-moyd sist)
A type of benign (not cancer) germ cell tumor (type of tumor that begins in the cells that give rise to sperm or eggs) that often contains several different types of tissue such as hair, muscle, and bone. Also called mature teratoma.

DES   
A synthetic form of the hormone estrogen that was prescribed to pregnant women between about 1940 and 1971 because it was thought to prevent miscarriages. DES may increase the risk of uterine, ovarian, or breast cancer in women who took it. It also has been linked to an increased risk of clear cell carcinoma of the vagina or cervix in daughters exposed to DES before birth. Also called diethylstilbestrol.

deslorelin   
A substance being studied in the treatment of cancer as a way to block sex hormones made by the ovaries or testicles. It is a type of gonadotropin-releasing hormone analog.

desmoid tumor    (DEZ-moyd TOO-mer)
A tumor of the tissue that surrounds muscles, usually in the abdomen. A desmoid tumor rarely metastasizes (spreads to other parts of the body). It may be called aggressive fibromatosis when the tumor is outside of the abdomen.

desmoplastic    (DES-moh-PLAS-tik)
Causing or forming adhesions or fibrous connective tissue within a tumor.

desmoplastic melanoma    (DES-moh-PLAS-tik MEH-luh-NOH-muh)
A rare form of malignant melanoma marked by nonpigmented lesions on sun-exposed areas of the body, most commonly on the head and neck.

desmoplastic small round cell tumor    (DES-moh-PLAS-tik ... TOO-mer)
A rare, aggressive cancer that usually affects young males and usually is located in the abdomen.

detoxify    (dee-TOX-ih-fy)
To make something less poisonous or harmful. It may refer to the process of removing toxins, poisons, or other harmful substances from the body.

developmental stage    (dee-VEH-lup-MEN-tul stayj)
The physical, mental, and emotional stages a child goes through as he or she grows and matures.

deviant    (DEE-vee-unt)
Different from what is normal or standard, especially in terms of behavior.

device    (deh-VISE)
An object that has a specific use. In medicine, wheelchairs, pumps, and artificial limbs are examples of devices.

DEXA   
An imaging test that measures bone density (the amount of bone mineral contained in a certain volume of bone) by passing x-rays with two different energy levels through the bone. It is used to diagnose osteoporosis (decrease in bone mass and density). Also called BMD scan, bone mineral density scan, DEXA scan, dual energy x-ray absorptiometric scan, dual x-ray absorptiometry, and DXA.

DEXA scan   
An imaging test that measures bone density (the amount of bone mineral contained in a certain volume of bone) by passing x-rays with two different energy levels through the bone. It is used to diagnose osteoporosis (decrease in bone mass and density). Also called BMD scan, bone mineral density scan, DEXA, dual energy x-ray absorptiometric scan, dual x-ray absorptiometry, and DXA.

dexamethasone    (DEK-suh-MEH-thuh-sone)
A synthetic steroid (similar to steroid hormones produced naturally in the adrenal gland). Dexamethasone is used to treat leukemia and lymphoma and may be used to treat some of the problems caused by other cancers and their treatment.

dexmethylphenidate   
A substance being studied in the treatment of fatigue and nervous system side effects caused by chemotherapy. It is a type of central nervous system stimulant.

dexrazoxane    (DEKS-ruh-ZOK-sane)
The active ingredient in a drug used to treat severe side effects caused by certain anticancer drugs. Under the brand name Totect it is used to treat the toxic effects of an anticancer drug that leaks from a vein into surrounding tissue and causes tissue damage. Under the brand name Zinecard it is used to reduce heart damage in women given doxorubicin for breast cancer that has spread. Dexrazoxane is also being studied in the treatment of cancer. It is a type of cardioprotective agent, a type of chemoprotective agent, and a type of topoisomerase inhibitor.

dexrazoxane hydrochloride    (DEKS-ruh-ZOK-sane HY-droh-KLOR-ide)
A drug used to treat severe side effects caused by certain anticancer drugs. It is used under the brand name Totect to treat the toxic effects of an anticancer drug that leaks from a vein into surrounding tissue and causes tissue damage. It is also used under the brand name Zinecard to reduce heart damage in women given doxorubicin for breast cancer that has spread. Dexrazoxane hydrochloride is also being studied in the treatment of cancer. It is a type of cardioprotective agent, a type of chemoprotective agent, and a type of topoisomerase inhibitor.

dextroamphetamine-amphetamine   
A combination of drugs used as a treatment for attention deficit hyperactivity disorder (ADHD) and narcolepsy (a sleep disorder). It is a type of stimulant. Also called Adderall.

dextromethorphan acetic acid    (DEK-stroh-meh-THOR-fan uh-SEE-tik A-sid)
An anticancer drug that is a type of angiogenesis inhibitor.

DFMO   
A substance being studied in the treatment of cancer. Also called difluoromethylornithine.

DHA-paclitaxel    (...PA-klih-TAK-sil)
A combination of DHA (a natural fatty acid) and paclitaxel (an anticancer drug) being studied in the treatment of cancer. It is a type of mitotic inhibitor.

DHEA   
A substance being studied in the prevention of cancer. It is a type of steroid. Also called dehydroepiandrosterone.

DHPLN   
A childhood condition in which abnormal tissue grows on the outer part of one or both kidneys. DHPLN usually develops into Wilms tumor (a type of childhood kidney cancer) if not treated. Also called diffuse hyperplastic perilobar nephroblastomatosis.

DHT   
A hormone made from testosterone in the prostate, testes, and certain other tissues. It is needed to develop and maintain male sex characteristics, such as facial hair, deep voice, and muscle growth. High amounts of DHT may increase the growth of prostate cancer and make it harder to treat. Also called androstanolone and dihydrotestosterone.

di-dgA-RFB4   
An anticancer drug that is a combination of a monoclonal antibody (RFB4) and an immunotoxin (dgA).

diabetes    (dy-uh-BEE-teez)
Any of several diseases in which the kidneys make a large amount of urine. Diabetes usually refers to diabetes mellitus in which there is also a high level of glucose (a type of sugar) in the blood because the body does not make enough insulin or use it the way it should.

diabetes mellitus    (dy-uh-BEE-teez MEL-ih-tus)
A disease in which the body does not control the amount of glucose (a type of sugar) in the blood and the kidneys make a large amount of urine. This disease occurs when the body does not make enough insulin or does not use it the way it should.

diagnosis    (DY-ug-NOH-sis)
The process of identifying a disease, such as cancer, from its signs and symptoms.

diagnostic mammogram   
X-ray of the breasts used to check for breast cancer after a lump or other sign or symptom of breast cancer has been found.

diagnostic procedure    (DY-ug-NAH-stik proh-SEE-jer)
A specific test or series of steps done to help diagnose a disease or condition. Mammograms and colonscopies are examples of diagnostic procedures.

diagnostic technique    (DY-ug-NAH-stik tek-NEEK)
A type of method or test used to help diagnose a disease or condition. Imaging tests and tests to measure blood pressure, pulse, and temperature are examples of diagnostic techniques.

diagnostic trial   
A research study that evaluates methods of detecting disease.

dialysis    (dye-AL-ih-sis)
The process of filtering the blood when the kidneys are not able to cleanse it.

diameter   
The length of a straight line that extends from one edge of a tumor or other object, through its center and to the opposite edge. It is usually used to measure the size of round or spherical shapes.

diaphragm    (DY-uh-fram)
The thin muscle below the lungs and heart that separates the chest from the abdomen.

diarrhea   
Frequent and watery bowel movements.

diathermy    (DY-uh-THER-mee)
A procedure in which tissue is heated to destroy abnormal cells. The heat may come from electric currents, microwaves, radio waves, or ultrasound. Diathermy is a type of hyperthermia therapy. Also called electrodiathermy.

diazepam    (dy-A-zeh-pam)
A drug used to treat mild to moderate anxiety and tension and to relax muscles. It is a type of benzodiazepine. Also called Valium.

diaziquone   
An anticancer drug that is able to cross the blood-brain barrier and kill cancer cells in the central nervous system. Also called AZQ.

diclofenac    (dy-KLOH-fen-ak)
The active ingredient in a drug that is used to treat the symptoms of rheumatoid arthritis and is being studied in the prevention and treatment of some types of skin cancer. It blocks substances that cause inflammation and pain. It may also prevent the growth of new blood vessels that tumors need to grow. It is a type of cyclooxygenase inhibitor, a type of nonsteroidal anti-inflammatory drug (NSAID), and a type of antiangiogenesis agent.

diclofenac sodium    (dy-KLOH-fen-ak SOH-dee-um)
A drug that is used to treat the symptoms of rheumatoid arthritis and is being studied in the prevention and treatment of some types of skin cancer. It blocks substances that cause inflammation and pain. It may also prevent the growth of new blood vessels that tumors need to grow. It is a type of cyclooxygenase inhibitor, a type of nonsteroidal anti-inflammatory drug (NSAID), and a type of antiangiogenesis agent. Also called Voltaren.

diclofenac sodium gel    (dy-KLOH-fen-ak SOH-dee-um JEL)
The gel form of a drug that is used to treat the symptoms of rheumatoid arthritis and is being studied in the prevention and treatment of some types of skin cancer. It blocks substances that cause inflammation and pain. It may also prevent the growth of new blood vessels that tumors need to grow. It is a type of cyclooxygenase inhibitor, a type of nonsteroidal anti-inflammatory drug (NSAID), and a type of antiangiogenesis agent. Also called Voltaren gel.

didanosine   
A drug used in the treatment of infections caused by viruses.

DIEP flap   
A type of breast reconstruction in which blood vessels called deep inferior epigastric perforators (DIEP), and the skin and fat connected to them are removed from the lower abdomen and used for reconstruction. Muscle is left in place.

diet   
The things a person eats and drinks.

dietary counseling    (DY-uh-TAYR-ee KOWN-suh-ling)
A process by which a health professional with special training in nutrition helps people make healthy food choices and form healthy eating habits. In cancer treatment, the goal of dietary counseling is to help patients stay healthy during and after treatment and to stay strong enough to fight infections and the recurrence of disease. Also called nutritional counseling.

dietary protocol    (DY-uh-TAYR-ee PROH-tuh-KOL)
A detailed diet plan that states what, how, and when a person will eat and drink. It may be used to test how a specific diet affects a health outcome, such as lower cholesterol.

Dietary Reference Intakes    (DY-uh-TAYR-ee REH-feh-rens ...)
A set of guidelines developed by U.S. and Canadian scientists to give information about the role of nutrients in human health. These guidelines include the Reference Daily Intakes (RDI), which are the recommended amounts of nutrients to be eaten each day to meet the needs of most healthy people. This system replaced the Recommended Dietary Allowances (RDA). Also called DRI.

dietary supplement    (DY-uh-TAYR-ee SUH-pleh-ment)
A product that is added to the diet. A dietary supplement is taken by mouth, and usually contains one or more dietary ingredient (such as vitamin, mineral, herb, amino acid, and enzyme). Also called nutritional supplement.

diethylstilbestrol    (dye-EH-thul-stil-BES-trol)
A synthetic form of the hormone estrogen that was prescribed to pregnant women between about 1940 and 1971 because it was thought to prevent miscarriages. Diethylstilbestrol may increase the risk of uterine, ovarian, or breast cancer in women who took it. It also has been linked to an increased risk of clear cell carcinoma of the vagina or cervix in daughters exposed to diethylstilbestrol before birth. Also called DES.

dietitian    (dy-eh-TIH-shun)
A health professional with special training in nutrition who can help with dietary choices. Also called nutritionist.

differentiation   
In cancer, refers to how mature (developed) the cancer cells are in a tumor. Differentiated tumor cells resemble normal cells and tend to grow and spread at a slower rate than undifferentiated or poorly differentiated tumor cells, which lack the structure and function of normal cells and grow uncontrollably.

diffuse    (dih-FYOOS)
Widely spread; not localized or confined.

diffuse hyperplastic perilobar nephroblastomatosis    (dih-FYOOS HY-per-PLAS-tik payr-ee-LOH-ber NEH-froh-blas-TOH-muh-TOH-sis)
A childhood condition in which abnormal tissue grows on the outer part of one or both kidneys. Diffuse hyperplastic perilobar nephroblastomatosis usually develops into Wilms tumor (a type of childhood kidney cancer) if not treated. Also called DHPLN.

diffuse intrinsic pontine glioma    (dih-FYOOS in-TRIN-sik PON-teen glee-OH-muh)
A type of central nervous system tumor that forms from glial (supportive) tissue of the brain and spinal cord. Diffuse intrinsic pontine glioma usually occurs in children. It forms in the brain stem.

diffuse large B-cell lymphoma    (dih-FYOOS larj ... sel lim-FOH-muh)
A type of B-cell non-Hodgkin lymphoma (cancer of the immune system) that is usually aggressive (fast-growing). It is the most common type of non-Hodgkin lymphoma, and is marked by rapidly growing tumors in the lymph nodes, spleen, liver, bone marrow, or other organs. Other symptoms include fever, night sweats, and weight loss. There are several subtypes of diffuse large B-cell lymphoma.

difluoromethylornithine   
A substance being studied in the treatment of cancer. Also called DFMO.

digestion    (dy-JES-chun)
The process of breaking down food into substances the body can use for energy, tissue growth, and repair.

digestive system    (dy-JES-tiv SIS-tem)
The organs that take in food and turn it into products that the body can use to stay healthy. Waste products the body cannot use leave the body through bowel movements. The digestive system includes the salivary glands, mouth, esophagus, stomach, liver, pancreas, gallbladder, small and large intestines, and rectum.

digestive tract    (dy-JES-tiv)
The organs through which food and liquids pass when they are swallowed, digested, and eliminated. These organs are the mouth, esophagus, stomach, small and large intestines, and rectum and anus.

digital image analysis    (DIH-jih-tul IH-mij uh-NA-lih-sis)
A method in which an image or other type of data is changed into a series of dots or numbers so that it can be viewed and studied on a computer. In medicine, this type of image analysis is being used to study organs or tissues, and in the diagnosis and treatment of disease.

digital mammography    (DIH-jih-tul ma-MAH-gruh-fee)
The use of a computer, rather than x-ray film, to create a picture of the breast.

digital photography    (DIH-jih-tul fuh-TAH-gruh-fee)
A type of photography in which images can be viewed on a computer screen.

digital rectal examination    (DIH-jih-tul REK-tul eg-ZA-mih-NAY-shun)
An examination in which a doctor inserts a lubricated, gloved finger into the rectum to feel for abnormalities. Also called DRE.

digitalis    (DIH-jih-TA-lis)
A substance used to make drugs that are used to treat several heart conditions, including congestive heart failure. Digitalis is made from the dried leaves of Digitalis purpurea (common foxglove) plants. It is a type of cardiac glycoside.

digoxin    (dih-JOK-sin)
A drug used to treat irregular heartbeat and some types of heart failure. It is also being studied in the treatment of some types of cancer. Digoxin helps the heart work normally by controlling the amount of calcium that goes into the heart muscle. It also may kill cancer cells and make them more sensitive to anticancer drugs. It is a type of cardiac glycoside. Also called Lanoxin.

dihematoporphyrin ether    (dy-HEE-muh-toh-POR-fih-rin EE-ther)
Used in photodynamic therapy, a drug that is absorbed by tumor cells; when exposed to light, it becomes active and kills the cancer cells.

dihydrotestosterone    (dy-HY-droh-tes-TOS-teh-RONE)
A hormone made from testosterone in the prostate, testes, and certain other tissues. It is needed to develop and maintain male sex characteristics, such as facial hair, deep voice, and muscle growth. High amounts of dihydrotestosterone may increase the growth of prostate cancer and make it harder to treat. Also called androstanolone and DHT.

diindolylmethane    (dy-IN-doh-lil-MEH-thayn)
A substance being studied in the treatment of prostate cancer and in the prevention of cervical cancer. Diindolylmethane is found in cruciferous vegetables like broccoli, brussels sprouts, cauliflower, cabbage, and kale. It is a type of plant indole. Also called DIM.

dilatation and curettage    (DIH-luh-TA-shun and KYUR-eh-TAHJ)
A procedure to remove tissue from the cervical canal or the inner lining of the uterus. The cervix is dilated (made larger) and a curette (spoon-shaped instrument) is inserted into the uterus to remove tissue. Also called D&C and dilation and curettage.

dilate    (DYE-late)
To widen or enlarge an opening or hollow structure beyond its usual size, such as the pupil of the eye or a blood vessel.

dilation and curettage    (DY-LAY-shun and KYUR-eh-TAHJ)
A procedure to remove tissue from the cervical canal or the inner lining of the uterus. The cervix is dilated (made larger) and a curette (spoon-shaped instrument) is inserted into the uterus to remove tissue. Also called D&C and dilatation and curettage.

dilator    (DYE-lay-tor)
A device used to stretch or enlarge an opening.

dilute    (dy-LOOT)
To make something thinner, weaker, less concentrated, or less pure by adding something to it.

DIM   
A substance being studied in the treatment of prostate cancer and in the prevention of cervical cancer. DIM is found in cruciferous vegetables like broccoli, brussels sprouts, cauliflower, cabbage, and kale. It is a type of plant indole. Also called diindolylmethane.

Dimericine    (dy-MAYR-ih-seen)
A lotion being studied in the treatment of skin cancer and a skin condition called xeroderma pigmentosum. It has an enzyme contained in very tiny, fat-like particles. The enzyme repairs damage caused by ultraviolet radiation. Dimericine is a type of DNA repair enzyme topical agent. Also called T4N5 liposomal lotion.

dimesna   
A drug that belongs to the family of drugs called chemoprotective agents.

dimethyl sulfoxide   
A colorless liquid that readily dissolves many chemicals and penetrates animal and plant tissues. It is used in human medicine, veterinary medicine, and pharmaceuticals.

dimethylxanthenone acetic acid    (DY-MEH-thil-ZAN-theh-none uh-SEE-tik A-sid)
An anticancer drug that is a type of angiogenesis inhibitor.

diphenhydramine    (dy-fen-HY-druh-meen)
A drug used to treat allergies and relieve cough and itching caused by insect bites, sunburn, and poison oak or ivy. It is also used to treat mild Parkinson disease, to prevent and treat motion sickness, to relieve cough and cold symptoms, and as a sleep aid. It is a type of antihistamine.

diphosphonate    (dy-FOS-foh-nayt)
A drug or substance used to treat hypercalcemia (abnormally high blood calcium) and bone pain caused by some types of cancer. Forms of diphosphonates are also used to treat osteoporosis and for bone imaging. Diphosphonates inhibit a type of bone cell that breaks down bone. Also called bisphosphonate.

dipyridamole   
A drug that prevents blood cell clumping and enhances the effectiveness of fluorouracil and other chemotherapeutic agents.

direct ophthalmoscopy    (… OP-thal-MOS-koh-pee)
An exam of the inside of the back of the eye using an ophthalmoscope (a flashlight-sized instrument with a light source and a set of rotating lenses).

discharge    (DIS-charj)
In medicine, a fluid that comes out of the body. Discharge can be normal or a sign of disease. Discharge also means release of a patient from care.

disease progression   
Cancer that continues to grow or spread.

disease-free survival    (dih-ZEEZ... ser-VY-vul)
The length of time after treatment for a specific disease during which a patient survives with no sign of the disease. Disease-free survival may be used in a clinical study or trial to help measure how well a new treatment works. Also called DFS and disease-free survival time.

disease-specific survival rate    (dih-ZEEZ-speh-SIH-fik ser-VY-vul ...)
The percentage of people in a study or treatment group who have not died from a specific disease in a defined period of time. The time period usually begins at the time of diagnosis or at the start of treatment and ends at the time of death. Patients who died from causes other than the disease being studied are not counted in this measurement.

disinfectant    (DIS-in-fek-tunt)
Any substance or process that is used primarily on non-living objects to kill germs, such as viruses, bacteria, and other microorganisms that can cause infection and disease. Most disinfectants are harsh chemicals but sometimes heat or radiation may be used.

disorder    (dis-OR-der)
In medicine, a disturbance of normal functioning of the mind or body. Disorders may be caused by genetic factors, disease, or trauma.

disorientation    (dis-OR-ee-en-TAY-shun)
A mental state marked by confusion about time, place, or who one is.

disseminate    (dih-SEH-mih-NATE)
Scatter or distribute over a large area or range.

distal   
In medicine, refers to a part of the body that is farther away from the center of the body than another part. For example, the fingers are distal to the shoulder. The opposite is proximal.

distal pancreatectomy    (DIS-tul PAN-kree-uh-TEK-toh-mee)
Removal of the body and tail of the pancreas.

distant cancer   
Refers to cancer that has spread from the original (primary) tumor to distant organs or distant lymph nodes. Also known as distant metastasis.

distant metastasis    (...meh-TAS-tuh-sis)
Refers to cancer that has spread from the original (primary) tumor to distant organs or distant lymph nodes. Also known as distant cancer.

distraction   
In medicine, a pain relief method that takes the patient's attention away from the pain.

distress    (dih-STRESS)
Extreme mental or physical pain or suffering.

disulfiram   
A drug that slows the metabolism of retinoids, allowing them to act over a longer period of time.

diuretic   
A drug that increases the production of urine.

diverticulitis    (DY-ver-TIH-kyoo-LY-tis)
Inflammation of one or more pouches or sacs that bulge out from the wall of a hollow organ, such as the colon. Symptoms include muscle spasms and cramps in the abdomen.

diverticulosis    (DY-ver-TIH- kyoo-LOH-sis)
A condition marked by small sacs or pouches in the walls of a hollow organ, such as the colon. These sacs can become inflamed and cause a condition called diverticulitis.

diverticulum    (DY-ver-TIH-kyoo-lum)
A small pouch or sac that bulges out from the wall of a hollow organ, such as the colon.

DJ-927   
A substance being studied in the treatment of cancer. It is a type of taxane derivative.

DNA   
The molecules inside cells that carry genetic information and pass it from one generation to the next. Also called deoxyribonucleic acid.

DNA gene-expression microarray    (… JEEN-ek-SPREH-shun MY-kroh-uh-RAY)
A process that allows thousands of pieces of DNA that are fixed to a glass slide to be analyzed at one time. It is used to identify the genes (pieces of DNA) in specific cells or tissue that are actively used to make RNA, which then may be used to make proteins.

DNA methylase    (… MEH-thih-LAYZ)
An enzyme (a protein that speeds up chemical reactions in the body) that attaches a methyl group to DNA. A methyl group is a chemical group containing one carbon and three hydrogen molecules. Also called DNA methyltransferase.

DNA methyltransferase    (... MEH-thul-TRANZ-fer-ayz)
An enzyme (a protein that speeds up chemical reactions in the body) that attaches a methyl group to DNA. A methyl group is a chemical group containing one carbon and three hydrogen molecules. Also called DNA methylase.

DNA replication    (… reh-plih-KAY-shun)
The process by which a copy of the DNA in a cell is made before the cell divides.

DNR order   
A type of advance directive in which a person states that healthcare providers should not perform cardiopulmonary resuscitation (restarting the heart) if his or her heart or breathing stops. Also called do not resuscitate order.

do not resuscitate order    (…ree-SUH-sih-TAYT…)
A type of advance directive in which a person states that healthcare providers should not perform cardiopulmonary resuscitation (restarting the heart) if his or her heart or breathing stops. Also called DNR order.

docetaxel    (doh-seh-TAK-sel)
A drug used together with other drugs to treat certain types of breast cancer, stomach cancer, prostate cancer, and certain types of head and neck cancer. It is also being studied in the treatment of other types of cancer. Docetaxel is a type of mitotic inhibitor. Also called Taxotere.

dock   
A plant that has been used in some cultures to treat certain medical problems. It may have anticancer effects. The scientific name is Rumex acetosella. Also called sheep sorrel and sorrel.

dolasetron    (doh-LAH-seh-tron)
The active ingredient in a drug used to treat nausea and vomiting caused by cancer treatment. Dolasetron is a type of serotonin receptor antagonist and a type of antiemetic.

dolasetron mesylate    (doh-LAH-seh-tron MEH-zih-layt)
A drug used to treat nausea and vomiting caused by cancer treatment. It is a type of serotonin receptor antagonist and a type of antiemetic. Also called Anzemet.

dolastatin 10    (DOH-luh-STA-tin …)
A substance being studied in the treatment of cancer. It binds to a protein that cells need to divide and it may kill cancer cells. Dolastatin 10 comes from a marine organism. It is a type of mitotic inhibitor.

donepezil    (doh-NEP-eh-zil)
A drug that is used to treat Alzheimer disease and is being studied in the treatment of side effects caused by radiation therapy to the brain. It is a type of cholinesterase inhibitor.

dong quai    (dahng-kwye)
An herb native to China. A substance taken from the roots has been used in traditional Chinese medicine to treat menstrual and menopausal problems. Dong quai may increase the effect of the drug warfarin (a blood-thinner). The scientific name is Angelica sinensis.

donor lymphocyte infusion    (DOH-ner LIM-foh-site in-FYOO-zhun)
A type of therapy in which lymphocytes from the blood of a donor are given to a patient who has already received a stem cell transplant from the same donor. The donor lymphocytes may kill remaining cancer cells. Donor lymphocyte infusion is used to treat chronic myelogenous leukemia (CML) that has come back and myeloma. It is being studied in the treatment of other types of cancer.

dornase alfa inhalation solution    (DOR-nayz AL-fuh in-huh-LAY-shun suh-LOO-shun)
A drug given in an aerosol mist to decrease the thickness of mucus in the lungs of patients with cystic fibrosis. It is also being studied as a treatment to reduce the thickness of saliva in patients being treated for head and neck cancer. Dornase alfa inhalation solution contains an enzyme that breaks the DNA in mucus into small pieces and makes the mucus thinner. Also called Pulmozyme.

dose   
The amount of medicine taken, or radiation given, at one time.

dose-dense chemotherapy    (DOSE-dents KEE-moh-THAYR-uh-pee)
A chemotherapy treatment plan in which drugs are given with less time between treatments than in a standard chemotherapy treatment plan.

dose-dependent   
Refers to the effects of treatment with a drug. If the effects change when the dose of the drug is changed, the effects are said to be dose-dependent.

dose-limiting   
Describes side effects of a drug or other treatment that are serious enough to prevent an increase in dose or level of that treatment.

dose-rate   
The strength of a treatment given over a period of time.

dosimetrist    (do-SIM-uh-trist)
A person who determines the proper radiation dose for treatment.

dosimetry    (doh-SIH-muh-tree)
Measurement of radiation exposure from x-rays, gamma rays, or other types of radiation used in the treatment or detection of diseases, including cancer.

double-blinded    (DUH-bul BLINE-ded)
A clinical trial in which the medical staff, the patient, and the people who analyze the results do not know the specific type of treatment the patient receives until after the clinical trial is over.

double-contrast barium enema   
A procedure in which x-rays of the colon and rectum are taken after a liquid containing barium is put into the rectum. Barium is a silver-white metallic compound that outlines the colon and rectum on an x-ray and helps show abnormalities. Air is put into the rectum and colon to further enhance the x-ray.

doubling time    (DUH-bling...)
In biology, the amount of time it takes for one cell to divide or for a group of cells (such as a tumor) to double in size. The doubling time is different for different kinds of cancer cells or tumors.

douche    (DOOSH)
A procedure in which water or a medicated solution is used to clean the vagina and cervix.

Down syndrome    (...SIN-drome)
A disorder caused by the presence of an extra chromosome 21 and characterized by mental retardation and distinguishing physical features.

Dox-SL   
A form of the anticancer drug doxorubicin that is contained in very tiny, fat-like particles. It may have fewer side effects and work better than doxorubicin. Dox-SL is used to treat ovarian cancer, AIDS-related Kaposi sarcoma, and multiple myeloma in patients whose disease has not gotten better after treatment with other anticancer drugs. It may be used together with other anticancer drugs. It is also being studied in the treatment of other types of cancer. Dox-SL is a type of anthracycline antitumor antibiotic. Also called Doxil, doxorubicin hydrochloride liposome, Evacet, and LipoDox.

doxazosin    (dox-AY-zoh-sin)
A drug used to treat high blood pressure and urinary problems caused by an enlarged prostate. It relaxes muscle tissue in blood vessels and in the prostate. Doxazosin is a type of alpha blocker. Also called Cardura and doxazosin mesylate.

doxazosin mesylate    (dox-AY-zoh-sin MEH-zih-layt)
A drug used to treat high blood pressure and urinary problems caused by an enlarged prostate. It relaxes muscle tissue in blood vessels and in the prostate. Doxazosin mesylate is a type of alpha blocker. Also called Cardura and doxazosin.

doxercalciferol    (DOK-ser-kal-SIH-feh-rol)
A substance being studied in the prevention of recurrent prostate cancer. It is a type of vitamin D analog.

Doxil    (DOK-sil)
A form of the anticancer drug doxorubicin that is contained in very tiny, fat-like particles. It may have fewer side effects and work better than doxorubicin. Doxil is used to treat ovarian cancer, AIDS-related Kaposi sarcoma, and multiple myeloma in patients whose disease has not gotten better after treatment with other anticancer drugs. It may be used together with other anticancer drugs. It is also being studied in the treatment of other types of cancer. Doxil is a type of anthracycline antitumor antibiotic. Also called Dox-SL, doxorubicin hydrochloride liposome, Evacet, and LipoDox.

doxorubicin    (DOK-soh-ROO-bih-sin)
A drug that is used to treat many types of cancer and is being studied in the treatment of other types of cancer. Doxorubicin comes from the bacterium Streptomyces peucetius. It damages DNA and may kill cancer cells. It is a type of anthracycline antitumor antibiotic. Also called Adriamycin PFS, Adriamycin RDF, doxorubicin hydrochloride, hydroxydaunorubicin, and Rubex.

doxorubicin hydrochloride    (DOK-soh-ROO-bih-sin HY-droh-KLOR-ide)
A drug that is used to treat many types of cancer and is being studied in the treatment of other types of cancer. Doxorubicin hydrochloride comes from the bacterium Streptomyces peucetius. It damages DNA and may kill cancer cells. It is a type of anthracycline antitumor antibiotic. Also called Adriamycin PFS, Adriamycin RDF, doxorubicin, hydroxydaunorubicin, and Rubex.

doxorubicin hydrochloride liposome    (DOK-soh-ROO-bih-sin HY-droh-KLOR-ide LY-poh-SOME)
A form of the anticancer drug doxorubicin that is contained in very tiny, fat-like particles. It may have fewer side effects and work better than doxorubicin. Doxorubicin hydrochloride liposome is used to treat ovarian cancer, AIDS-related Kaposi sarcoma, and multiple myeloma in patients whose disease has not gotten better after treatment with other anticancer drugs. It may be used together with other anticancer drugs. It is also being studied in the treatment of other types of cancer. Doxorubicin hydrochloride liposome is a type of anthracycline antitumor antibiotic. Also called Dox-SL, Doxil, Evacet, and LipoDox.

doxycycline   
An antibiotic drug used to treat infection.

DPA   
A type of power of attorney. A power of attorney is a legal document that gives one person (such as a relative, lawyer, or friend) the authority to make legal, medical, or financial decisions for another person. It may go into effect right away, or when that person is no longer able to make decisions for himself or herself. A DPA remains in effect until the person who grants it dies or cancels it. It does not need to be renewed over time. Also called durable power of attorney.

DPPE   
Belongs to a group of antihormone drugs.

DR4   
A protein on the surface of certain cells that binds another protein called TRAIL, which may kill some cancer cells. An increase in the amount or activity of DR4 on cancer cells may kill more cells. Also called death receptor 4, TRAIL receptor 1, TRAIL-R1, and tumor necrosis factor receptor superfamily member 10A.

DR5   
A protein on the surface of certain cells that binds another protein called TRAIL, which may kill some cancer cells. An increase in the amount or activity of DR5 on cancer cells may kill more cells. Also called death receptor 5, TRAIL receptor 2, TRAIL-R2, and tumor necrosis factor receptor superfamily member 10B.

drain   
In medicine, to remove fluid as it collects; or, a tube or wick-like device used to remove fluid from a body cavity, wound, or infected area.

DRE   
An examination in which a doctor inserts a lubricated, gloved finger into the rectum to feel for abnormalities. Also called digital rectal examination.

DRI   
A set of guidelines developed by U.S. and Canadian scientists to give information about the role of nutrients in human health. These guidelines include the Reference Daily Intakes (RDI), which are the recommended amounts of nutrients to be eaten each day to meet the needs of most healthy people. This system replaced the Recommended Dietary Allowances (RDA). Also called Dietary Reference Intakes.

dronabinol   
A synthetic pill form of delta-9-tetrahydrocannabinol (THC), an active ingredient in marijuana that is used to treat nausea and vomiting associated with cancer chemotherapy.

droperidol    (droh-PAYR-ih-dol)
A drug used to prevent nausea and vomiting in patients who receive anesthesia before surgery. It is also used to treat anxiety. Droperidol is a type of antiemetic, adjunct anesthesia, and antipsychotic.

drug   
Any substance, other than food, that is used to prevent, diagnose, treat or relieve symptoms of a disease or abnormal condition. Also refers to a substance that alters mood or body function, or that can be habit-forming or addictive, especially a narcotic.

drug abuse    (...uh-BYOOS)
The use of illegal drugs or the use of prescription or over-the-counter drugs for purposes other than those for which they are meant to be used, or in large amounts. Drug abuse may lead to social, physical, emotional, and job-related problems.

Drug Accountability Record    (… uh-KOWN-tuh-BIH-lih-tee …)
A log of study drugs kept by an investigator running a clinical trial. It lists many things about each drug, including the drug name, lot number, expiration date, the amount of drug received, used, returned, or thrown away, and the amount left. Drug Accountability Records help make sure that a clinical trial is done safely and correctly. Drug Accountability Records are required by the U.S. Food and Drug Administration (FDA). Also called DAR.

drug interaction    (… IN-ter-AK-shun)
A change in the way a drug acts in the body when taken with certain other drugs, herbals, or foods, or when taken with certain medical conditions. Drug interactions may cause the drug to be more or less effective, or cause effects on the body that are not expected.

drug resistance   
The failure of cancer cells, viruses, or bacteria to respond to a drug used to kill or weaken them. The cells, viruses, or bacteria may be resistant to the drug at the beginning of treatment, or may become resistant after being exposed to the drug.

drug therapy    (… THAYR-uh-pee)
Treatment with any substance, other than food, that is used to prevent, diagnose, treat, or relieve symptoms of a disease or abnormal condition.

drug tolerance   
A condition that occurs when the body gets used to a medicine so that either more medicine is needed or different medicine is needed.

dry orgasm   
Sexual climax without the release of semen from the penis.

DSMB   
Data and Safety Monitoring Board. An impartial group that oversees a clinical trial and reviews the results to see if they are acceptable. This group determines if the trial should be changed or closed. Also called Data and Safety Monitoring Board.

DT388IL3 fusion protein    (...FYOO-zhun PROH-teen)
A substance being studied in the treatment of myeloid leukemia (a disease in which too many immature non-lymphocyte white blood cells are found in the blood and bone marrow). DT388IL3 fusion protein is made by combining IL-3 with a toxic substance. The IL-3 attaches to the cancer cells and the toxic substance kills them.

DTGM fusion protein   
An anticancer drug formed by the combination of diphtheria toxin and a colony-stimulating factor (GM-CSF). The colony-stimulating factor is attracted to cancer cells, and the diphtheria toxin kills the cells.

DTH   
An inflammatory response that develops 24 to 72 hours after exposure to an antigen that the immune system recognizes as foreign. This type of immune response involves mainly T cells rather than antibodies (which are made by B cells). Also called delayed-type hypersensitivity response.

DTIC-Dome   
A drug that is used to treat Hodgkin lymphoma and malignant melanoma and is being studied in the treatment of other types of cancer. It attaches to DNA in cells and may kill cancer cells. It is a type of alkylating agent. Also called dacarbazine.

DU 145   
A cell line made from human prostate cancer cells that is used in the laboratory to study the way prostate cancer cells grow.

dual energy x-ray absorptiometric scan    (... ub-SORP-shee-uh-MEH-trik SKAN)
An imaging test that measures bone density (the amount of bone mineral contained in a certain volume of bone) by passing x-rays with two different energy levels through the bone. It is used to diagnose osteoporosis (decrease in bone mass and density). Also called BMD scan, bone mineral density scan, DEXA, DEXA scan, dual x-ray absorptiometry, and DXA.

dual x-ray absorptiometry    (... ub-SORP-shee-AH-meh-tree)
An imaging test that measures bone density (the amount of bone mineral contained in a certain volume of bone) by passing x-rays with two different energy levels through the bone. It is used to diagnose osteoporosis (decrease in bone mass and density). Also called BMD scan, bone mineral density scan, DEXA, DEXA scan, dual energy x-ray absorptiometric scan, and DXA.

duct    (dukt)
In medicine, a tube or vessel of the body through which fluids pass.

ductal carcinoma   
The most common type of breast cancer. It begins in the cells that line the milk ducts in the breast.

ductal carcinoma in situ    (DUK-tul KAR-sih-NOH-muh in SYE-too)
A noninvasive condition in which abnormal cells are found in the lining of a breast duct. The abnormal cells have not spread outside the duct to other tissues in the breast. In some cases, ductal carcinoma in situ may become invasive cancer and spread to other tissues, although it is not known at this time how to predict which lesions will become invasive. Also called DCIS and intraductal carcinoma.

ductal lavage    (DUK-tul luh-VAHZ)
A method used to collect cells from milk ducts in the breast. A hair-size catheter (tube) is inserted into the nipple, and a small amount of salt water is released into the duct. The water picks up breast cells, and is removed. The cells are checked under a microscope. Ductal lavage may be used in addition to clinical breast examination and mammography to detect breast cancer.

Dukes A colorectal cancer   
Cancer has spread beyond the innermost lining of the colon and/or rectum to the second and third layers and involves the inside wall of the colon and/or rectum, but it has not spread to the outer wall or outside the colon and/or rectum. Also called stage I colorectal cancer.

Dukes B colorectal cancer   
Cancer has spread outside the colon and/or rectum to nearby tissue, but it has not gone into the lymph nodes. Also called stage II colorectal cancer.

Dukes C colorectal cancer   
Tumor cells have spread to organs and lymph nodes near the colon/rectum. Also called stage III colorectal cancer.

Dukes classification   
A staging system used to describe the extent of colorectal cancer. Stages range from A (early stage) to D (advanced stage).

Dukes D colorectal cancer   
Cancer may have spread to nearby lymph nodes and has spread to other parts of the body, such as the liver or lungs. Also called stage IV colorectal cancer.

duloxetine    (duh-LOX-uh-teen)
A drug used to treat depression and peripheral neuropathy (pain, numbness, tingling, burning, or weakness in the hands or feet) that can occur with diabetes. It is also being studied in the treatment of peripheral neuropathy caused by certain anticancer drugs. Duloxetine increases the amount of certain chemicals in the brain that help relieve depression and pain. It is a type of serotonin and norepinephrine reuptake inhibitor. Also called Cymbalta and duloxetine hydrochloride.

duloxetine hydrochloride    (duh-LOX-uh-teen HY-droh-KLOR-ide)
A drug used to treat depression and peripheral neuropathy (pain, numbness, tingling, burning, or weakness in the hands or feet) that can occur with diabetes. It is also being studied in the treatment of peripheral neuropathy caused by certain anticancer drugs. Duloxetine hydrochloride increases the amount of certain chemicals in the brain that help relieve depression and pain. It is a type of serotonin and norepinephrine reuptake inhibitor. Also called Cymbalta and duloxetine.

dumping syndrome   
A condition that occurs when food or liquid moves too fast into the small intestine. Symptoms include cramps, nausea, diarrhea, sweating, weakness, and dizziness. Dumping syndrome sometimes occurs in people who have had part or all of their stomach removed.

duodenitis   
Inflammation of the duodenum (the first part of the small intestine that connects to the stomach).

duodenum    (doo-ah-DEE-num)
The first part of the small intestine that connects to the stomach.

durable power of attorney    (DUR-uh-bul...uh-TER-nee)
A type of power of attorney. A power of attorney is a legal document that gives one person (such as a relative, lawyer, or friend) the authority to make legal, medical, or financial decisions for another person. It may go into effect right away, or when that person is no longer able to make decisions for himself or herself. A durable power of attorney remains in effect until the person who grants it dies or cancels it. It does not need to be renewed over time. Also called DPA.

dutasteride    (duh-TAS-ter-ide)
A drug used to treat symptoms of an enlarged prostate gland. It is being studied in the treatment of male hair loss and prostate cancer. Dutasteride blocks enzymes the body needs to make male sex hormones. It is a type of 5-alpha reductase inhibitor. Also called Avodart and GG745.

DVT   
The formation of a blood clot in a deep vein of the leg or lower pelvis. Symptoms may include pain, swelling, warmth, and redness in the affected area. Also called deep vein thrombosis.

DX-52-1   
An anticancer drug that is a type of antitumor antibiotic. It is an anthracycline.

DX-8951f   
An anticancer drug that is a type of topoisomerase inhibitor. Also called exatecan mesylate.

DXA   
An imaging test that measures bone density (the amount of bone mineral contained in a certain volume of bone) by passing x-rays with two different energy levels through the bone. It is used to diagnose osteoporosis (decrease in bone mass and density). Also called BMD scan, bone mineral density scan, DEXA, DEXA scan, dual energy x-ray absorptiometric scan, and dual x-ray absorptiometry.

dyscrasia   
Disease. Usually refers to diseases of the blood.

dysesthesia    (DIS-es-THEE-zhuh)
A condition in which a sense, especially touch, is distorted. Dysesthesia can cause an ordinary stimulus to be unpleasant or painful. It can also cause insensitivity to a stimulus.

dysfunction    (dis-FUNK-shun)
A state of not functioning normally.

dysgeusia   
A bad taste in the mouth. Also called parageusia.

dyspepsia   
Upset stomach.

dysphagia   
Difficulty swallowing.

dysphonia    (diss-FOH-nee-uh)
Trouble with the voice when trying to talk, including hoarseness and change in pitch or quality or voice.

dysplasia    (dis-PLAY-zhuh)
Cells that look abnormal under a microscope but are not cancer.

dysplastic nevus    (dis-PLAS-tik NEE-vus)
A type of nevus (mole) that looks different from a common mole. A dysplastic nevus is often larger with borders that are not easy to see. Its color is usually uneven and can range from pink to dark brown. Parts of the mole may be raised above the skin surface. A dysplastic nevus may develop into malignant melanoma (a type of skin cancer).

dyspnea    (DISP-nee-uh)
Difficult, painful breathing or shortness of breath.

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