E7070: A drug that belongs to the family of drugs called sulfonamides. It is being studied for its ability to treat cancer.

echocardiography: A procedure that uses ultrasonic waves directed over the chest wall to obtain a graphic record of the heart's position, motion of the walls, or internal parts such as the valves.

ecteinascidin 743: An anticancer drug that inhibits the growth of cancer cells by disrupting the structure of tumor-cell DNA.

edatrexate: An anticancer drug that belongs to a family of drugs called antimetabolites.

edema (eh-DEE-ma): Swelling caused by excess fluid in body tissues.

edrecolomab: A type of monoclonal antibody used in cancer detection or therapy. Monoclonal antibodies are laboratory-produced substances that can locate and bind to cancer cells.

EF5: A drug that is used to plan cancer treatment by measuring oxygen levels in tumor cells.

effector cell: A cell that performs a specific function in response to a stimulus; usually used to describe cells in the immune system.

eflornithine: An antiprotozoal drug that is being studied for cancer prevention.

ejaculation: The release of semen through the penis during orgasm.

electrodesiccation (e-LEK-tro-des-ih-KAY-shun): The drying of tissue by a high-frequency electric current applied with a needle-shaped electrode.

electrolarynx (e-LEK-tro-LAIR-inks): A battery-operated instrument that makes a humming sound. An electrolarynx is used to help people whose voice boxes (larynxes) have been removed.

electrolytes (eh-LEK-tro-lites): Substances that break up into ions (electrically charged particles) when they are dissolved in body fluids or water. Some examples are sodium, potassium, chloride, and calcium. Electrolytes are primarily responsible for the movement of nutrients into cells, and the movement of wastes out of cells.

electron microscope: A microscope (device used to magnify small objects) that uses electrons (instead of light) to produce an enlarged image. An electron microscopes shows tiny details better than any other type of microscope.

electroporation therapy: EPT. Treatment that generates electrical pulses through an electrode placed in a tumor to enhance the ability of anticancer drugs to enter tumor cells.

embolism (EM-bul-izm): A block in an artery caused by blood clots or other substances, such as fat globules, infected tissue, or cancer cells.

embolization (EM-bo-lih-ZAY-shun): The blocking of an artery by a clot or foreign material. Embolization can be done as treatment to block the flow of blood to a tumor.

embryo: Having to do with an early stage in the development of a plant or an animal. In vertebrate animals, this stage lasts from shortly after fertilization until all major body parts appear. In particular, in humans, this stage lasts from about 2 weeks after fertilization until the end of the seventh or eighth week of pregnancy.

EMD 121974: A substance that is being studied as an anticancer and antiangiogenesis drug.

emitefur: An anticancer drug that belongs to the family of drugs called antimetabolites.

emphysema: Pulmonary emphysema is a disorder affecting the alveoli (tiny air sacs) of the lungs. The transfer of oxygen and carbon dioxide in the lungs takes place in the walls of the alveoli. In emphysema, the alveoli become abnormally inflated, damaging their walls and making it harder to breathe. People who smoke or have chronic bronchitis have an increased risk of emphysema.

enalapril: An antihypertensive agent that can also be used to slow or prevent the progression of heart disease in people with childhood cancer treated with drugs that may be harmful to the heart.

encapsulated (en-KAP-soo-lay-ted): Confined to a specific, localized area and surrounded by a thin layer of tissue.

encephalopathy: A disorder of the brain that can be caused by disease, injury, drugs, or chemicals.

enchondroma (en-kon-DRO-ma): A benign (noncancerous) growth of cartilage in bones or in other areas where cartilage is not normally found.

endocervical curettage (en-do-SER-vih-kul kyoo-reh-TAHZH): The scraping of the mucous membrane of the cervical canal using a spoon-shaped instrument called a curette.

endocrine cancer: Cancer that occurs in endocrine tissue, the tissue in the body that secretes hormones.

endocrinologist (en-do-krih-NAH-lo-jist): A doctor that specializes in diagnosing and treating hormone disorders.

endogenous: Produced inside an organism or cell. The opposite is external (exogenous) production.

endometrial: Having to do with the endometrium (the layer of tissue that lines the uterus).

endometrial disorder: Abnormal cell growth in the endometrium (the lining of the uterus).

endometriosis (en-do-mee-tree-O-sis): A benign condition in which tissue that looks like endometrial tissue grows in abnormal places in the abdomen.

endometrium (en-do-MEE-tree-um): The layer of tissue that lines the uterus.

endoscope (EN-do-skope): A thin, lighted tube used to look at tissues inside the body.

endoscopic retrograde cholangiopancreatography (en-do-SKAH-pik RET-ro-grade ko-LAN-jee-o-PAN-kree-a-TAW-gra-fee): ERCP. A procedure to x-ray the pancreatic duct, hepatic duct, common bile duct, duodenal papilla, and gallbladder. In this procedure, a thin, lighted tube (endoscope) is passed through the mouth and down into the first part of the small intestine (duodenum). A smaller tube (catheter) is then inserted through the endoscope into the bile and pancreatic ducts. A dye is injected through the catheter into the ducts, and an x-ray is taken.

endoscopy (en-DAHS-ko-pee): The use of a thin, lighted tube (called an endoscope) to examine the inside of the body.

endostatin: A drug that is being studied for its ability to prevent the growth of new blood vessels into a solid tumor. Endostatin belongs to the family of drugs called angiogenesis inhibitors.

endothelial cell: The main type of cell found in the inside lining of blood vessels, lymph vessels, and the heart.

enema: The injection of a liquid through the anus into the large bowel.

eniluracil: An anticancer drug that increases the effectiveness of fluorouracil. Also called ethynyluracil.

enoxaparin: A drug used to prevent blood clots. It belongs to the family of drugs called anticoagulants.

enterostomal therapist (en-ter-o-STO-mul): A health professional trained in the care of persons with urostomies and other stomas.

environmental tobacco smoke: ETS. Smoke that comes from the burning of a tobacco product and smoke that is exhaled by smokers (second-hand smoke). Inhaling ETS is called involuntary or passive smoking.

enzyme: A protein that speeds up chemical reactions in the body.

ependymal tumors: A type of brain tumor that usually begins in the central canal of the spinal cord. Ependymomas may also develop in the cells lining the ventricles of the brain, which produce and store the special fluid (cerebrospinal fluid) that protects the brain and spinal cord. Also called ependymomas.

ependymomas: Brain tumors that usually begin in the central canal of the spinal cord. Ependymomas may also develop in the cells lining the ventricles of the brain, which produce and store the special fluid (cerebrospinal fluid) that protects the brain and spinal cord. Also called ependymal tumors.

epidermal growth factor receptor: EGFR. The protein found on the surface of some cells and to which epidermal growth factor binds, causing the cells to divide. It is found at abnormally high levels on the surface of many types of cancer cells, so these cells may divide excessively in the presence of epidermal growth factor. Also known as ErbB1 or HER1.

epidermis (ep-i-DER-mis): The upper or outer layer of the two main layers of tissue that make up the skin.

epidermoid carcinoma (ep-i-DER-moyd kar-sin-O-ma): A type of cancer in which the cells are flat and look like fish scales. Also called squamous cell carcinoma.

epidural: The space between the wall of the spinal canal and the covering of the spinal cord. An epidural injection is given into this space.

epidural block: An injection of an anesthetic drug into the space between the wall of the spinal canal and the covering of the spinal cord.

epigastric: Having to do with the upper middle area of the abdomen.

epiglottis (ep-ih-GLAH-tis): The flap that covers the trachea during swallowing so that food does not enter the lungs.

epilepsy: A group of disorders marked by problems in the normal functioning of the brain. These problems can produce seizures, unusual body movements, a loss of consciousness or changes in consciousness, as well as mental problems or problems with the senses.

epinephrine: A hormone and neurotransmitter. Also called adrenaline.

epirubicin: An anticancer drug that belongs to the family of drugs called antitumor antibiotics.

epithelial (ep-ih-THEE-lee-ul): Refers to the cells that line the internal and external surfaces of the body.

epithelial carcinoma (ep-ih-THEE-lee-ul kar-sin-O-ma): Cancer that begins in the cells that line an organ.

epithelial ovarian cancer (ep-ih-THEE-lee-ul): Cancer that occurs in the cells lining the ovaries.

epithelium (EP-ih-THEE-lee-um): A thin layer of tissue that covers organs, glands, and other structures within the body.

epoetin alfa: A colony-stimulating factor that is made in the laboratory. It increases the production of red blood cells.

Epstein-Barr virus: EBV. A common virus that remains dormant in most people. It has been associated with certain cancers, including Burkitt's lymphoma, immunoblastic lymphoma, and nasopharyngeal carcinoma.

ERA-923: A substance that is being studied as a treatment for cancer. It belongs to a family of drugs called antiestrogens.

erb-38 immunotoxin: A toxic substance linked to an antibody that attaches to tumor cells and kills them.

ERCP: Endoscopic retrograde cholangiopancreatography (en-do-SKAH-pik RET-ro-grade ko-LAN-jee-o-PAN-kree-a-TAW-gra-fee). A procedure to x-ray the bile and pancreatic ducts. In this procedure, a thin, lighted tube (endoscope) is passed through the mouth and down into the first part of the small intestine (duodenum). A smaller tube (catheter) is then inserted through the endoscope into the bile and pancreatic ducts. A dye is injected through the catheter into the ducts, and an x-ray is taken.

erythrocytes (eh-RITH-ro-sites): Cells that carry oxygen to all parts of the body. Also called red blood cells (RBCs).

erythroleukemia (eh-RITH-ro-loo-KEE-mee-a): Cancer of the blood-forming tissues in which large numbers of immature, abnormal red blood cells are found in the blood and bone marrow.

erythroplakia (eh-RITH-ro-PLAY-kee-a): A reddened patch with a velvety surface found in the mouth.

erythropoietin: Produced in the adult kidney, a colony-stimulating factor that stimulates the production of red blood cells.

esophageal (eh-SOF-a-JEE-al): Having to do with the esophagus, the muscular tube through which food passes from the throat to the stomach.

esophageal speech (eh-SOF-a-JEE-al): Speech produced by trapping air in the esophagus and forcing it out again. It is used by people whose voice boxes (larynxes) have been removed.

esophagectomy (eh-sof-a-JEK-toe-mee): An operation to remove a portion of the esophagus.

esophagitis: Inflammation of the esophagus (the tube that carries food from the mouth to the stomach).

esophagoscopy (eh-sof-a-GAHS-ko-pee): Examination of the esophagus using a thin, lighted tube.

esophagram (eh-SOF-a-gram): A series of x-rays of the esophagus. The x-ray pictures are taken after the person drinks a solution that contains barium. The barium coats and outlines the esophagus on the x-ray. Also called a barium swallow.

esophagus (eh-SOF-a-gus): The muscular tube through which food passes from the throat to the stomach.

estramustine: A combination of the hormone estradiol (an estrogen) and nitrogen mustard (an anticancer drug). Used in the palliative therapy of prostate cancer.

estrogen receptor: ER. Protein found on some cancer cells to which estrogen will attach.

estrogen receptor negative: ER-. Breast cancer cells that do not have a protein (receptor molecule) to which estrogen will attach. Breast cancer cells that are ER- do not need the hormone estrogen to grow and usually do not respond to hormone (antiestrogen) therapy that blocks these receptor sites.

estrogen receptor positive: ER+. Breast cancer cells that have a protein (receptor molecule) to which estrogen will attach. Breast cancer cells that are ER+ need the hormone estrogen to grow and will usually respond to hormone (antiestrogen) therapy that blocks these receptor sites.

estrogen replacement therapy: ERT. Hormones (estrogen, progesterone, or both) given to postmenopausal women or to women who have had their ovaries surgically removed. Hormones are given to replace the estrogen no longer produced by the ovaries.

estrogens (ES-tro-jins): A family of hormones that promote the development and maintenance of female sex characteristics.

etanidazole: A drug that increases the effectiveness of radiation therapy.

ethynyluracil: An anticancer drug that increases the effectiveness of fluorouracil. Also called eniluracil.

etidronate: A drug that belongs to the family of drugs called bisphosphonates. Bisphosphonates are used as treatment for hypercalcemia (abnormally high levels of calcium in the blood) and for cancer that has spread to the bone (bone metastases).

etiology: The cause or origin of disease.

etoposide: An anticancer drug that is a podophyllotoxin derivative and belongs to the family of drugs called mitotic inhibitors.

evaluable disease: Disease that cannot be measured directly by the size of the tumor but can be evaluated by other methods specific to a particular clinical trial.

evaluable patients: Patients whose response to a treatment can be measured because enough information has been collected.

Ewing's sarcoma (YOO-ingz sar-KO-ma): A type of bone cancer that usually forms in the middle (shaft) of large bones. Also called Ewing's sarcoma/primitive neuroectodermal tumor (PNET).

exatecan mesylate: An anticancer drug that belongs to the family of drugs called topoisomerase inhibitors. Also called DX-8951f.

excisional biopsy (ek-SI-zhun-al BY-op-see): A surgical procedure in which an entire lump or suspicious area is removed for diagnosis. The tissue is then examined under a microscope.

exemestane: An anticancer drug used to decrease estrogen production and suppress the growth of estrogen-dependent tumors.

exisulind: A drug that is being studied in the treatment and prevention of cancer. It has been shown to cause apoptosis (cell death) in cancerous and precancerous cells by acting through a group of cellular enzymes called cGMP phosphodiesterases.

extensive-stage small cell lung cancer: Cancer that has spread outside the lung to other tissues in the chest or to other parts of the body.

external radiation (ray-dee-AY-shun): Radiation therapy that uses a machine to aim high-energy rays at the cancer. Also called external-beam radiation.

external-beam radiation (ray-dee-AY-shun): Radiation therapy that uses a machine to aim high-energy rays at the cancer. Also called external radiation.