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Glossary - T


Showing 1-48 out of 48 Terms

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  • T cell

    (... sel)

    A type of white blood cell. T cells are part of the immune system and develop from stem cells in the bone marrow. They help protect the body from infection and may help fight cancer. Also called T lymphocyte and thymocyte.

  • T–cell ALL

    (T-sel ...)

    T-cell acute lymphoblastic leukemia. An aggressive (fast-growing) type of leukemia (blood cancer) in which too many T-cell lymphoblasts (immature white blood cells) are found in the bone marrow and blood. Also called precursor T-lymphoblastic leukemia and T-cell acute lymphocytic leukemia.

  • T Lymphocytes

    (… LIM-foh-site)

    A type of white blood cell. T lymphocytes are part of the immune system and develop from stem cells in the bone marrow. They help protect the body from infection and may help fight cancer. Also called T cell and thymocyte.

  • Targeted therapy

    (TAR-geh-ted THAYR-uh-pee)

    A type of treatment that uses drugs or other substances to identify and attack specific types of cancer cells with less harm to normal cells. Some targeted therapies block the action of certain enzymes, proteins, or other molecules involved in the growth and spread of cancer cells. Other types of targeted therapies help the immune system kill cancer cells or deliver toxic substances directly to cancer cells and kill them. Targeted therapy may have fewer side effects than other types of cancer treatment. Most targeted therapies are either small molecule drugs or monoclonal antibodies.

  • Temperature

    A measurement of the heat in a person's body.

  • Temperature spike

    When your temperature suddenly becomes elevated or goes up.

  • Term Pronunciation

    Term Description

  • Testes


    Two egg-shaped glands inside the scrotum that produce sperm and male hormones. Also called testicles.

  • Testicles


    Two egg-shaped glands inside the scrotum that produce sperm and male hormones. Also called testes.

  • Testicular mass

    A swelling of your testis or testicle, the male reproductive gland.

  • Testosterone


    A hormone made mainly in the testes (part of the male reproductive system). It is needed to develop and maintain male sex characteristics, such as facial hair, deep voice, and muscle growth. Testosterone may also be made in the laboratory and is used to treat certain medical conditions.

  • Therapeutic medical play

    (THAYR-uh-PYOO-tik MEH-dih-kul …)

    The use of games, toys, books, art, and role playing, sometimes with real or pretend medical equipment, to help children understand and become more comfortable with medical tests, procedures, treatments, and their illness. Therapeutic medical play gives children a way to express their feelings, fears, and anxieties and helps them learn ways to cope with things that may be stressful or upsetting.

  • Thioguanine


    A drug used to treat acute myeloid leukemia (AML). It is also being studied in the treatment of other types of cancer. Thioguanine stops cells from making DNA and RNA and it may kill cancer cells. It is a type of antimetabolite. Also called Tabloid.

  • Thoracentesis


    Removal of fluid from the pleural cavity through a needle inserted between the ribs.

  • Thrombocytopenia


    A condition in which there is a lower-than-normal number of platelets in the blood. It may result in easy bruising and excessive bleeding from wounds or bleeding in mucous membranes and other tissues.

  • Thrombophlebitis


    Inflammation of a vein that occurs when a blood clot forms.

  • Thrombosis


    The formation or presence of a thrombus (blood clot) inside a blood vessel.

  • Thymus


    An organ that is part of the lymphatic system, in which T lymphocytes grow and multiply. The thymus is in the chest behind the breastbone.

  • Thyroid


    A gland located beneath the larynx (voice box) that makes thyroid hormone and calcitonin. The thyroid helps regulate growth and metabolism. Also called thyroid gland.

  • Thyroid cancer

    (THY-royd KAN-ser)

    Cancer that forms in the thyroid gland (an organ at the base of the throat that makes hormones that help control heart rate, blood pressure, body temperature, and weight). Four main types of thyroid cancer are papillary, follicular, medullary, and anaplastic thyroid cancer. The four types are based on how the cancer cells look under a microscope.

  • Thyroid Gland


    A gland located beneath the larynx (voice box) that makes thyroid hormone and calcitonin. The thyroid gland helps regulate growth and metabolism. Also called thyroid.

  • Thyroid stimulating hormone

    (THY-royd STIM-yoo-LAY-ting HOR-mone)

    A hormone produced by the pituitary gland. Thyroid-stimulating hormone stimulates the release of thyroid hormone from thyroglobulin. It also stimulates the growth of thyroid follicular cells. An abnormal thyroid-stimulating hormone level may mean that the thyroid hormonal regulation system is out of control, usually as a result of a benign condition (hyperthyroidism or hypothyroidism).

  • Thyroxine


    A hormone that is made by the thyroid gland and contains iodine. Thyroxine increases the rate of chemical reactions in cells and helps control growth and development. Thyroxine can also be made in the laboratory and is used to treat thyroid disorders. Also called L-3,5,5-tetraiodothyronine, T4, and thyroxin.

  • Tinnitus


    Ringing in your ears.

  • Tissue

    A group or layer of cells that work together to perform a specific function.

  • Tonsils


    Two small masses of lymphoid tissue on either side of the throat.

  • Toxicity


    The extent to which something is poisonous or harmful.

  • Toxins

    A poison made by certain bacteria, plants, or animals, including insects.

  • Tracer


    A substance (such as a radioisotope) used in imaging procedures.

  • Trachea


    The airway that leads from the larynx (voice box) to the bronchi (large airways that lead to the lungs). Also called windpipe.

  • Tracheostomy


    Surgery to create an opening (stoma) into the windpipe. The opening itself may also be called a tracheostomy.

  • Transfusion reaction

    An allergic response to blood products. You may experience hives, chills or headaches.

  • Transplantation


    A surgical procedure in which tissue or an organ is transferred from one area of a persons body to another area, or from one person (the donor) to another person (the recipient).

  • Transsphenoidal surgery

    (TRANS-sfee-NOY-dul SER-juh-ree)

    A type of surgery in which instruments are inserted through the nose and sphenoid sinus (a hollow space in a bone in the nose) to remove tumors that are in or near the pituitary gland. The pituitary gland is a pea-sized organ that lies at the base of the brain above the back of the nose.

  • Treatments

    The action or manner of caring for a patient medically or surgically.

  • Triglycerides

    Triglycerides are a type of fat. They are the most common type of fat in your body. They come from foods, especially butter, oils, and other fats you eat. Triglycerides also come from extra calories. These are the calories that you eat, but your body does not need right away. Your body changes these extra calories into triglycerides, and stores them in fat cells. When your body needs energy, it releases the triglycerides. Having a high level of triglycerides can raise your risk of heart diseases, such as coronary artery disease.

  • Trisomy 18

    (TRY-soh-mee …)

    A genetic disorder caused by having an extra chromosome 18 in some or all of the bodys cells. Trisomy 18 is marked by a low birth weight and certain abnormal features. These include a small, abnormally shaped head; a small jaw and mouth; clenched fists with overlapping fingers; and heart, lung, kidney, intestine, and stomach defects. Many babies with trisomy 18 die before birth or within the first month of life, but some children live for several years. Having trisomy 18 increases the risk of certain types of cancer, such as hepatoblastoma (a type of liver cancer) and Wilms tumor (a type of kidney cancer). Also called Edwards syndrome.

  • Tuberculosis


    A disease caused by a specific type of bacteria that spreads from one person to another through the air. Tuberculosis can affect many parts of the body, but most often affects the lungs. A person may not have symptoms of tuberculosis for years, but they may appear when the patient becomes ill with a serious condition like diabetes, AIDS, or cancer. Tuberculosis can usually be treated and cured with antibiotics. Also called TB.

  • Tuberous Sclerosis

    (TOO-ber-us skleh-ROH-sis)

    A genetic disorder in which benign (not cancer) tumors form in the kidneys, brain, eyes, heart, lungs, and skin. This disease can cause seizures, mental disabilities, and different types of skin lesions.

  • Tumor


    An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancer), or malignant (cancer). Also called neoplasm.

  • Tumor grade

    (TOO-mer grayd)

    A description of a tumor based on how abnormal the cancer cells and tissue look under a microscope and how quickly the cancer cells are likely to grow and spread. Low-grade cancer cells look more like normal cells and tend to grow and spread more slowly than high-grade cancer cells. Grading systems are different for each type of cancer. They are used to help plan treatment and determine prognosis. Also called grade and histologic grade.

  • Tumor lysis syndrome

    (TOO-mer LY-sis SIN-drome)

    A condition that can occur after treatment of a fast-growing cancer, especially certain leukemias and lymphomas (cancers of the blood). As tumor cells die, they break apart and release their contents into the blood. This causes a change in certain chemicals in the blood, which may cause damage to organs, including the kidneys, heart, and liver.

  • Tumor marker

    (TOO-mer MAR-ker)

    A substance found in tissue, blood, bone marrow, or other body fluids that may be a sign of cancer or certain benign (noncancer) conditions.

  • Tumor markers

    (TOO-mer MAR-kers)

    A substance found in tissue, blood, bone marrow, or other body fluids that may be a sign of cancer or certain benign (noncancer) conditions. Many tumor markers are proteins made by both normal cells and cancer cells, but they are made in higher amounts by cancer cells. Genetic changes in tumor tissue, such as gene mutations, patterns of gene expression, and other changes in tumor DNA or RNA, are also being used as tumor markers. A tumor marker may be used with other tests to help diagnose cancer. It may also be used to help plan treatment, give a likely prognosis, and find out how well treatment is working or if cancer has come back. Examples of tumor markers include CA-125 (in ovarian cancer), estrogen receptor and progesterone receptor (in breast cancer), CEA (in colon cancer), PCA3 mRNA and PSA (in prostate cancer), and EGFR gene mutation (in non-small cell lung cancer).

  • Turcot syndrome

    (ter-KOH SIN-drome)

    A rare, inherited disorder in which polyps (abnormal growths of tissue) form on the inside walls of the colon and rectum, and tumors form in the brain. There are two types of Turcot syndrome, which are caused by mutations (changes) in different genes. People with Turcot syndrome have a higher-than-normal risk of colorectal cancer and brain cancer, especially glioblastoma and medulloblastoma.

  • Turner syndrome

    (TER-ner SIN-drome)

    A genetic condition that occurs in females who have a missing or abnormal X chromosome (sex chromosome). Turner syndrome is marked by a shorter-than-average height, ovaries that do not function normally, and infertility. Other signs and symptoms may include extra folds of skin on the neck, a low hairline at the back of the neck, swelling of the hands and feet, and heart, kidney, bone, and hearing problems. Turner syndrome is present at birth but its signs and symptoms may occur slowly over time. Having Turner syndrome increases the risk of germ cell tumors in the ovaries.

  • Tyrosine kinase inhibitor

    (TY-ruh-seen KY-nays in-HIH-bih-ter)

    A substance that blocks the action of enzymes called tyrosine kinases. Tyrosine kinases are a part of many cell functions, including cell signaling, growth, and division. These enzymes may be too active or found at high levels in some types of cancer cells, and blocking them may help keep cancer cells from growing. Some tyrosine kinase inhibitors are used to treat cancer. They are a type of targeted therapy.

  • Tyrosinemia


    A rare, inherited disorder marked by high blood levels of a protein building block called tyrosine. This can cause a harmful buildup of tyrosine and other substances in the bodys tissues and organs, especially in the liver, kidney, and nervous system. This can lead to serious medical problems and may increase the risk of liver cancer. Tyrosinemia is caused by mutations (changes) in certain genes that make enzymes needed to break down tyrosine.