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-s (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.

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 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.

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 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 ode an organism or cell. The opposite is external (exogenous) production.