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Glossary - A


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  • Abdomen


    The area of the body that contains the pancreas, stomach, intestines, liver, gallbladder, and other organs.

  • Ablative therapy

    Treatment that removes or destroys the function of an organ or system. For example, high dose chemotherapy and radiation before a bone marrow transplant is considered ablative therapy because it wipes out your immune system.

  • Abnormal


    Not normal. Describes a state, condition, or behavior that is unusual or different from what is considered normal. An abnormal lesion or growth in or on the body may be benign (not cancer), precancerous or premalignant (likely to become cancer), or malignant (cancer).

  • Absolute neutrophil count

    (AB-soh-loot NOO-troh-fil kownt)

    A measure of the number of neutrophils in the blood. Neutrophils are a type of white blood cell. They help the body fight infection. An absolute neutrophil count may be used to check for infection, inflammation, leukemia, and other conditions. The lower a person's absolute neutrophil count is, the higher the risk is of getting an infection. Having an absolute neutrophil count of less than 500 means there is a high risk of getting an infection. Cancer treatment, such as chemotherapy, may reduce the absolute neutrophil count. Also called ANC.

  • Acupressure


    The application of pressure or localized massage to specific sites on the body to control symptoms such as pain or nausea. It is a type of complementary and alternative medicine.

  • Acupuncture


    The technique of inserting thin needles through the skin at specific points on the body to control pain and other symptoms. It is a type of complementary and alternative medicine.

  • Acute lymphoblastic leukemia

    (uh-KYOOT LIM-foh-BLAS-tik loo-KEE-mee-uh)

    A type of leukemia (blood cancer) that comes on quickly and is fast growing. In acute lymphoblastic leukemia, there are too many lymphoblasts (immature white blood cells) in the blood and bone marrow. Also called acute lymphocytic leukemia and ALL.

  • Acute lymphocytic leukemia

    uh-KYOOT LIM-foh-SIH-tik loo-KEE-mee-uh

    A type of leukemia (blood cancer) that comes on quickly and is fast growing. In acute lymphocytic leukemia, there are too many lymphoblasts (immature white blood cells) in the blood and bone marrow. Also called acute lymphoblastic leukemia and ALL.

  • Acute myeloid leukemia

    uh-KYOOT MY-eh-loyd loo-KEE-mee-uh

    An aggressive (fast-growing) disease in which too many myeloblasts (immature white blood cells that are not lymphoblasts) are found in the bone marrow and blood. Also called acute myeloblastic leukemia, acute myelogenous leukemia, acute nonlymphocytic leukemia, AML, and ANLL.

  • Addison disease

    (A-dih-sun dih-ZEEZ)

    A rare disorder in which the adrenal glands do not make enough of certain hormones. Symptoms include weight loss, loss of appetite, nausea and vomiting, diarrhea, muscle weakness, fatigue, low blood sugar, low blood pressure, and patchy or dark skin. Most cases of the disorder are caused by immune system problems, but may also be caused by infection, cancer, or other diseases. Also called adrenal insufficiency.

  • Adjuvant therapy

    (A-joo-vunt THAYR-uh-pee)

    Additional cancer treatment given after the primary treatment to lower the risk that the cancer will come back. Adjuvant therapy may include chemotherapy, radiation therapy, hormone therapy, targeted therapy, or biological therapy.

  • Adrenal gland


    A small gland that makes steroid hormones, adrenaline, and noradrenaline. These hormones help control heart rate, blood pressure, and other important body functions. There are two adrenal glands, one on top of each kidney. Also called suprarenal gland.

  • Adrenal glands


    A small gland that makes steroid hormones, adrenaline, and noradrenaline. These hormones help control heart rate, blood pressure, and other important body functions. There are two adrenal glands, one on top of each kidney. Also called suprarenal gland.

  • Adrenocortical tumor

    (uh-DREE-noh-KOR-tih-kul TOO-mer)

    A rare cancer that forms in the outer layer of tissue of the adrenal gland (a small organ on top of each kidney that makes steroid hormones, adrenaline, and noradrenaline to control heart rate, blood pressure, and other body functions). Also called adrenocortical carcinoma and cancer of the adrenal cortex.

  • Adrenocorticotropic hormone

    (uh-DREE-noh-KOR-tih-koh-TROH-pik HOR-mone)

    A hormone made in the pituitary gland. Adrenocorticotropic hormone acts on the outer part of the adrenal gland to control its release of corticosteroid hormones. More adrenocorticotropic hormone is made during times of stress. Also called ACTH and corticotropin.

  • Advance directive

    A legal document that states the treatment or care a person wishes to receive or not receive if he or she becomes unable to make medical decisions (for example, due to being unconscious).

  • Afebrile

    Having no fever, normal temperature.

  • Aggressive


    In medicine, describes a tumor or disease that forms, grows, or spreads quickly.

  • Alagille syndrome

    (a-luh-JEEL SIN-drome)

    A rare disorder in which there are defects in the small tubes that carry bile (fluid that helps digest fat) out of the liver. These small tubes may be narrow or have an abnormal shape, or there may be fewer of them than normal. This can cause bile to build up in the liver, which may lead to cirrhosis (scarring of the liver) and liver damage. Alagille syndrome can also affect other parts of the body, including the heart, kidneys, blood vessels, eyes, face, and spine. It usually occurs in infants and children and may be inherited.

  • Albumin


    A type of protein found in blood, egg white, milk, and other substances.

  • Aldosterone


    A steroid hormone made by the adrenal cortex (the outer layer of the adrenal gland). It helps control the balance of water and salts in the kidney by keeping sodium in and releasing potassium from the body. Too much aldosterone can cause high blood pressure and a build-up of fluid in body tissues. Aldosterone is a type of mineralocorticoid hormone.

  • Alkylating agents

    (AL-kuh-LAY-ting AY-jents)

    A type of drug that is used in the treatment of cancer.

  • Allergen


    A substance that causes an allergic response. Examples include pollen, molds, and certain foods.

  • Allogeneic


    Taken from different individuals of the same species. Also called allogenic.

  • Alopecia


    The lack or loss of hair from areas of the body where hair is usually found. Alopecia can be a side effect of some cancer treatments.

  • Alpha-fetoprotein


    A protein normally produced by a fetus. Alpha-fetoprotein levels are usually undetectable in the blood of healthy adult men or women (who are not pregnant). An elevated level of alpha-fetoprotein suggests the presence of either a primary liver cancer or germ cell tumor. Also called AFP.

  • Alternative therapy

    Non-conventional treatment that may not be medically proven. Some alternative therapies may have dangerous or even life-threatening side effects. With others, the main danger is that you may lose the opportunity to benefit from conventional therapy. It is recommended that you discuss the use of alternative therapies with your health care team.

  • Ambulatory

    The ability to walk; not confined to bed.

  • Aminoglycoside antibiotics

    (uh-MEE-noh-GLY-koh-side AN-tee-by-AH-tik)

    A substance that works against many types of bacteria and includes streptomycin, gentamicin, and neomycin. An aminoglycoside antibiotic is used to treat bacterial infections.

  • Amputation


    The removal by surgery of a limb (arm or leg) or other body part because of injury or disease, such as diabetes or cancer.

  • Analgesic


    A drug that reduces pain. Analgesics include aspirin, acetaminophen, and ibuprofen.

  • Anaphylactic shock

    (A-nuh-fih-LAK-tik shok)

    A severe and sometimes life-threatening immune system reaction to an antigen that a person has been previously exposed to. The reaction may include itchy skin, edema, collapsed blood vessels, fainting, difficulty in breathing, and death.

  • Androgen


    A type of hormone that promotes the development and maintenance of male sex characteristics.

  • Anemia

    Low red blood cell count which can cause you to feel fatigued and have shortness of breath. Anemia can be caused by a variety of conditions and diseases.

  • Anesthesia

    General or local medicine provided to permit the performance of surgery or other painful procedures.

  • Anesthesiologist


    A doctor who specializes in giving medicines or other agents that prevent or relieve pain, especially during surgery.

  • Anesthetic


    A drug or other substance that causes a loss of feeling or awareness. Local anesthetics cause a loss of feeling in one small area of the body. Regional anesthetics cause a loss of feeling in a part of the body, such as an arm or leg. General anesthetics cause a loss of feeling and a complete loss of awareness that feels like a very deep sleep.

  • Aneurysm

    An aneurysm is a bulge or "ballooning" in the wall of an artery. Arteries are blood vessels that carry oxygen-rich blood from the heart to other parts of the body. If an aneurysm grows large, it can burst and cause dangerous bleeding or even death. Most aneurysms occur in the aorta, the main artery that runs from the heart through the chest and abdomen. Aneurysms also can happen in arteries in the brain, heart and other parts of the body. If an aneurysm in the brain bursts, it causes a stroke.

  • Angiofibroma


    A benign (not cancer) tumor that is made up of blood vessels and fibrous (connective) tissue. Angiofibromas usually appear as small, red bumps on the face, especially on the nose and cheeks. They are common in patients with tuberous sclerosis (a genetic disorder that causes skin lesions, seizures, and mental problems). Angiofibromas are a type of vascular tumor.

  • Anorexia


    Loss of appetite, which may be caused by either the cancer itself or treatments such as chemotherapy.

  • Anorexia nervosa

    (a-nuh-REK-see-uh ner-VOH-suh)

    An eating disorder marked by an intense fear of gaining weight, a refusal to maintain a healthy weight, and a distorted body image. People with anorexia nervosa have an abnormal loss of appetite for food, try to avoid eating, and eat as little as possible.

  • Anthracycline


    A type of antibiotic that comes from certain types of Streptomyces bacteria. Anthracyclines are used to treat many types of cancer. Anthracyclines damage the DNA in cancer cells, causing them to die. Daunorubicin, doxorubicin, and epirubicin are anthracyclines.

  • Anthracyclines

    A type of antibiotic that comes from certain types of Streptomyces bacteria. Anthracyclines are used to treat many types of cancer. Anthracyclines damage the DNA in cancer cells, causing them to die. Daunorubicin, doxorubicin, and epirubicin are anthracyclines.

  • Antibiotic


    Drug used to kill organisms that cause disease. Since some cancer treatments can reduce your body's ability to fight infection, antibiotics may be used to treat or prevent (prophylactic) these infections.

  • Antibodies


    Antibodies are proteins that your immune system makes to fight foreign substances.

  • Antibody


    A protein produced by immune system cells and released into the blood. Antibodies defend against foreign agents, such as bacteria. These agents contain certain substances called antigens. Each antibody works against a specific antigen.

  • Antibody Therapy

    (AN-tee-BAH-dee THAYR-uh-pee)

    Treatment that uses antibodies to help the body fight cancer, infection, or other diseases. Antibodies are proteins made by the immune system that bind to specific markers on cells or tissues. Monoclonal antibodies are a type of antibody made in the laboratory that can be used in diagnosis or treatment. In cancer treatment, monoclonal antibodies may kill cancer cells directly, they may block development of tumor blood vessels, or they may help the immune system kill cancer cells.

  • Anticoagulant


    Drug that reduces the blood's ability to clot.

  • Anticonvulsant


    A drug or other substance used to prevent or stop seizures or convulsions. Also called antiepileptic.

  • Antiemetic


    A drug that prevents or relieves nausea and vomiting, common side effects of chemotherapy.

  • Antifungal


    A medicine that kills fungi, organisms that cause infections. Kids undergoing treatment for cancer are especially vulnerable to fungal infections.

  • Antigen


    Any substance that causes the body to make an immune response against that substance. Antigens include toxins, chemicals, bacteria, viruses, or other substances that come from outside the body. Body tissues and cells, including cancer cells, also have antigens on them that can cause an immune response. These antigens can also be used as markers in laboratory tests to identify those tissues or cells.

  • Antihistamine


    A medicine used to relieve the symptoms of allergies like hives, stuffy nose, etc.

  • Antimetabolite


    A drug that is very similar to natural chemicals in a normal biochemical reaction in cells but different enough to interfere with the normal division and functions of cells.

  • Antimicrobial


    A substance that kills microorganisms such as bacteria or mold, or stops them from growing and causing disease.

  • Antioxidants


    Compounds that hold back chemical reactions with oxygen (oxidation) and are thought to reduce the risk of some cancers. Examples are vitamins C and E and beta-carotene.

  • Antitumor


    Having to do with stopping abnormal cell growth.

  • Antiviral


    A drug used to treat infections caused by viruses.

  • Anus


    The opening of the rectum to the outside of the body.

  • Anxiety


    Feelings of fear, dread, and uneasiness that may occur as a reaction to stress. A person with anxiety may sweat, feel restless and tense, and have a rapid heart beat. Extreme anxiety that happens often over time may be a sign of an anxiety disorder.

  • Anxiety Disorder

    (ang-ZY-eh-tee dis-OR-der)

    A condition in which a person has excessive worry and feelings of fear, dread, and uneasiness. Other symptoms may include sweating, restlessness, irritability, fatigue, poor concentration, trouble sleeping, trouble breathing, a fast heartbeat, and dizziness. The symptoms can get worse over time and affect a persons day-to-day life. Anxiety disorders may be caused by a medical problem, a traumatic or stressful event, certain medicines, or other factors. There are many types of anxiety disorders, including generalized anxiety disorder, social anxiety disorder, panic disorder, post-traumatic stress disorder, and phobia-related disorders.

  • Aphasia


    Total or partial loss of the ability to use or understand language; usually caused by stroke, brain disease, or injury.

  • Apheresis


    A procedure in which blood is collected, part of the blood such as platelets or white blood cells is taken out, and the rest of the blood is returned to the donor. Also called pheresis.

  • Aplastic anemia

    AY-PLAS-tik uh-NEE-mee-uh

    A condition in which the bone marrow is unable to produce blood cells.

  • Apoptosis


    A type of cell death in which a series of molecular steps in a cell lead to its death. This is one method the body uses to get rid of unneeded or abnormal cells. The process of apoptosis may be blocked in cancer cells. Also called programmed cell death.

  • Appetite


    A desire to satisfy a physical or mental need, such as for food, sex, or adventure.

  • Arginine


    One of the twenty common amino acids (building blocks of proteins). Arginine is being studied as a nutritional supplement in the treatment and prevention of cancer and other conditions. Also called L-arginine.

  • Aromatherapy


    A type of complementary and alternative medicine that uses plant oils that give off strong pleasant aromas (smells) to promote relaxation, a sense of well-being, and healing.

  • Arterial blood gas

    The amount of oxygen in your blood.

  • Artery


    A vessel that carries oxygen-rich blood from your heart to the tissues. Blood is under pressure in arteries.

  • Aseptic Necrosis

    (ay-SEP-tik neh-KROH-sis)

    A condition in which there is a loss of blood flow to bone tissue, which causes the bone to die. It is most common in the hips, knees, shoulders, and ankles. It may be caused by long-term use of steroid medicines, alcohol abuse, joint injuries, and certain diseases, such as cancer and arthritis. It may also occur at some point in time after cancer treatment that included methotrexate, bisphosphonates, or corticosteroids. Also called avascular necrosis, ischemic necrosis, and osteonecrosis.

  • Aspartate Transaminase

    (as-PAR-tayt tranz-A-mih-nays)

    An enzyme found in the liver, heart, and other tissues. A high level of aspartate transaminase released into the blood may be a sign of liver or heart damage, cancer, or other diseases. Also called serum glutamic-oxaloacetic transaminase and SGOT.

  • Aspergillosis


    An infectious fungal disease that occurs most often in the skin, ears, nasal sinuses, and lungs of people with suppressed immune systems.

  • Aspergillus


    Fungi commonly found in soil. Certain types of Aspergillus may cause disease, especially in people who have suppressed immune systems.

  • Aspirate


    Refers to fluid, tissue, or other substance that is withdrawn from a body cavity, cyst, or tumor. Refers to the act of withdrawing the fluid, tissue, or other substance through a needle. It also refers to the accidental breathing in of food or fluid into the lungs. This can cause serious problems, such as pneumonia and other lung problems.

  • Aspiration


    To draw out by suction.

  • Assent process

    (uh-SENT PRAH-ses)

    A process that is required by law in which children or adolescents are given easy-to-understand information about a clinical trial to help them decide if they want to take part in the trial. The patient is given a chance to ask questions about what will happen during the trial, why its being done, and what they will be asked to do. Formal consent to enter the trial comes from the parent or guardian.

  • Astrocytes


    A large, star-shaped cell that holds nerve cells in place and helps them develop and work the way they should. An astrocyte is a type of glial cell.

  • Ataxia


    Loss of muscle coordination.

  • Ataxia-telangiectasia


    A rare, inherited, progressive, degenerative disease of childhood that causes loss of muscle control, a weakened immune system, and an increased risk of cancer.

  • Attending Physician

    (uh-TEN-ding fih-ZIH-shun)

    A medical doctor who is responsible for the overall care of a patient in a hospital or clinic setting. An attending physician may also supervise and teach medical students, interns, and residents involved in the patients care.

  • Attenuated


    Weakened or thinned. Attenuated strains of disease-causing bacteria and viruses are often used as vaccines. The weakened strains are used as vaccines because they stimulate a protective immune response while causing no disease or only mild disease in the person receiving the vaccine.

  • Atypical teratoid/rhabdoid tumor

    (RAB-doyd TOO-mer)

    An aggressive cancer of the central nervous system, kidney, or liver that occurs in very young children. Also called AT/RT and ATT/RHT.

  • Audiogram

    A diagnostic test that is done to evaluate your hearing.

  • Auditory


    Having to do with the ear and the sense of hearing.

  • Auto syringe

    A portable pump to administer medications subcutaneously or intravenously over several days. This allows you to be ambulatory.

  • Autoimmune disease

    (AW-toh-ih-MYOON dih-ZEEZ)

    A condition in which the body recognizes its own tissues as foreign and directs an immune response against them.

  • Autoimmune diseases

    A condition in which the body recognizes its own tissues as foreign and directs an immune response against them.

  • Autologous bone marrow transplant

    (aw-TAH-luh-gus bone MAYR-oh tranz-plan-TAY-shun)

    When your own bone marrow is used.

  • Autonomic Nervous System

    (AW-toh-NAH-mik NER-vus SIS-tem)

    The part of the nervous system that controls muscles of internal organs (such as the heart, blood vessels, lungs, stomach, and intestines) and glands (such as salivary glands and sweat glands). One part of the autonomic nervous system helps the body rest, relax, and digest food and another part helps a person fight or take flight in an emergency. Also called ANS and involuntary nervous system.

  • Avelox


    A drug used to treat bacterial infections. It is a type of fluoroquinolone. Also called moxifloxacin and moxifloxacin hydrochloride.

  • Avoidance


    The act of staying away from people, places, and thoughts that may cause anxiety, pain, or unpleasant feelings. Some types of cancer-related avoidance include refusing to accept a cancer diagnosis or get treatment, and using alcohol or other drugs to forget about having cancer.

  • Axillary


    Pertaining to the armpit area, including the lymph nodes that are located there.