Medical Glossary T

T-cell lymphoma (lim-FO-ma): A cancer of the immune system that appears in the skin; also called mycosis fungoides.

Testicles (TES-ti-kuls): The two egg-shaped glands that produce sperm and male hormones.

Testicular cancer: Cancer of the testicle (also called the testis), a rare kind of cancer in men, is a disease in which cancer (malignant) cells are found in the tissues of one or both testicles. The testicles are round and a little smaller than golf balls. Sperm (the male germ cells that can join with a female egg to develop into a baby) and male hormones are made in the testicles. There are two testicles located inside of the scrotum (a sac of loose skin that lies directly under the penis).

Testosterone (tes-TOS-ter-own): A male sex hormone.

Thermography (ther-MOG-ra-fee): A test to measure and display heat patterns of tissues near the surface of the breast. Abnormal tissue generally is warmer than healthy tissue. This technique is under study; its value in detecting breast cancer has not been proven.

Thoracentesis (thor-a-sen-TEE-sis): Removal of fluid in the pleura through a needle.

Thoracic (thor-ASS-ik): Pertaining to the chest.

Thoracotomy (thor-a-KOT-o-mee): An operation to open the chest.

Thrombocytes (THROM-bo-sites): See Platelets.

Thrombophlebitis (throm-bo-fleh-BYE-tis): Inflammation of a vein that occurs when a blood clot forms.

Thymoma: Malignant thymoma is a disease in which cancer (malignant) cells are found in the tissues of the thymus. The thymus is a small organ that lies under the breastbone. It makes white blood cells called lymphocytes, which travel through your body and fight infection. People with malignant thymoma often have other diseases of their immune system. The most common disease in people with thymoma is one in which the muscles are weak, called myasthenia gravis.

Thymus: An organ in which lymphocytes mature and multiply. It lies behind the breastbone.

Thyroid cancer: Cancer of the thyroid is a disease in which cancer (malignant) cells are found in the tissues of the thyroid gland. Your thyroid gland is at the base of your throat. It has two lobes, one on the right side and one on the left. Your thyroid gland makes important hormones that help your body to function normally.

Tissue (TISH-oo): A group or layer of cells that together perform specific functions.

Tonsils: Small masses of lymphatic tissue on either side of the throat.

Topical chemotherapy (kee-mo-THER-a-pee): Treatment with anticancer drugs in a lotion or cream.

Total pancreatectomy (pan-cree-a-TEK-to-mee): Surgery to remove the entire pancreas.

Toxins: Poisons produced by certain animals, plants, or bacteria.

Trachea (TRAY-kee-a): The airway that leads from the larynx to the lungs. Also called the windpipe.

Tracheoesophageal puncture (TRAY-kee-o-eh-SOF-a-JEE-al PUNK-chur): A small opening made by a surgeon between the esophagus and the trachea. A valve keeps food out of the trachea but lets air into the esophagus for esophageal speech.

Tracheostomy (TRAY-kee-AHS-toe-mee): Surgery to create an opening (stoma) into the windpipe. The opening itself may also be called a tracheostomy.

Tracheostomy button (TRAY-kee-AHS-toe-mee): A 1 to 1-1/2-inch-long plastic tube placed in the stoma to keep it open.

Tracheostomy tube (TRAY-kee-AHS-toe-mee): A 2- to 3-inch-long metal or plastic tube that keeps the stoma and trachea open. Also called a trach ("trake") tube.

Transformation: The change that a normal cell undergoes as it becomes malignant.

Transfusion (trans-FYOO-zhun): The transfer of blood or blood products from one person to another.

Transitional cell carcinoma: Cancer that develops in the lining of the renal pelvis. This type of cancer also occurs in the ureter and the bladder.

Transitional cells: Cells lining some organs.

Transplantation (trans-plan-TAY-shun): The replacement of an organ with one from another person.

Transrectal ultrasound: The use of sound waves to detect cancer. An instrument is inserted into the rectum. Waves bounce off the prostate and the pattern of the echoes produced is converted into a picture by a computer.

Transurethral resection (TRANZ-yoo-REE-thral ree-SEK-shun): Surgery performed with a special instrument inserted through the urethra. Also called TUR.

Transurethral resection of the prostate (TRANZ-yoo-REE-thral): The use of an instrument inserted through the penis to remove tissue from the prostate. Also called TUR or TURP.

Transvaginal ultrasound: Sound waves sent out by a probe inserted in the vagina. The waves bounce off the ovaries, and a computer uses the echoes to create a picture called a sonogram. Also called TVS.

Tumor (TOO-mer): An abnormal mass of tissue that results from excessive cell division. Tumors perform no useful body function. They may either be benign (not cancerous) or malignant (cancerous).

Tumor debulking: Surgically removing as much of the tumor as possible.

Tumor marker: A substance in blood or other body fluids that may suggest that a person has cancer.

Tumor necrosis factor (ne-KRO-sis): A type of biological response modifier (a substance that can improve the body's natural response to disease). Scientists are still learning how this substance causes cancer cells to die.

Tumor-suppressor gene: Genes in the body that can suppress or block the development of cancer.

Tumors of unknown primary origin: This is a disease in which cancer (malignant) cells are found somewhere in the body, but the place where they first started growing (the origin or primary site) cannot be found.