Tamoxifen (Tamoxifen Citrate)
A drug used to treat certain types of breast cancer in women and men, to prevent invasive breast cancer in women who have had ductal carcinoma in situ (abnormal cells in the ducts of the breast), and to prevent breast cancer in women who are at a high risk of developing the disease. It is also being studied in the treatment of other types of cancer. Tamoxifen citrate blocks the effects of the hormone estrogen in breast tissue, which may help keep breast cancer cells from growing. It is a type of selective estrogen receptor modulator (SERM). Tamoxifen is the active ingredient of tamoxifen citrate. Also called Soltamox.
Targeted Therapy
A type of treatment that uses drugs or other substances to target specific molecules that cancer cells need to survive and spread. Targeted therapies work in different ways to treat cancer. Some stop cancer cells from growing by interrupting signals that cause them to grow and divide, stopping signals that help form blood vessels, delivering cell-killing substances to cancer cells, or starving cancer cells of hormones they need to grow. Other targeted therapies help the immune system kill cancer cells or directly cause cancer cell death. Most targeted therapies are either small-molecule drugs or monoclonal antibodies. Also called molecularly targeted therapy. Trastuzumab (Herceptin) is an example of a targeted therapy used to treat breast cancer.
Therapeutic Touch
An integrative or complementary therapy where trained practitioners enter a semi-meditative state and hold their hands just above a person’s body to sense energy imbalances due to illness. Healing energy is then said to transfer to the person. Also called healing touch.
Thermography
In medicine, a procedure in which a heat-sensing infrared camera is used to record the surface heat produced by different parts of the body. Abnormal tissue growth can cause temperature changes, which may show up on the thermogram. Thermography may be used to diagnose breast cancer and other tumors.
Tissue
A group or layer of cells that work together to perform a specific function.
Tomosynthesis (see Breast Tomosynthesis in B)
Total Mastectomy (Simple Mastectomy)
Surgery to remove the whole breast, which may include the nipple, areola (the dark-colored skin around the nipple), and skin over the breast. Some of the lymph nodes under the arm may also be removed to check for cancer. Also called simple mastectomy.
Trastuzumab (Herceptin)
A drug used alone or with other drugs to treat certain types of breast cancer, stomach cancer, and gastroesophageal junction cancer that are HER2 positive. It is also being studied in the treatment of other types of cancer. Herceptin binds to a protein called HER2, which is found on some cancer cells. This may help the immune system kill cancer cells. Herceptin is a type of monoclonal antibody and a type of HER2 receptor antagonist. Also called Herzuma, Kanjinti, Ogivri, Ontruzant, trastuzumab, and Trazimera.
Triple Negative Breast Cancer (TNBC)
A type of breast cancer in which the tumor cells do not have estrogen receptors, progesterone receptors, or large amounts of HER2/neu protein on their surface. Knowing whether breast cancer is triple negative is important in planning treatment. Also called ER-negative PR-negative HER2/neu-negative breast cancer and TNBC.
Tumor
An abnormal mass of tissue that forms when cells grow and divide more than they should or do not die when they should. Tumors may be benign (not cancer) or malignant (cancer). Benign tumors may grow large but do not spread into, or invade, nearby tissues or other parts of the body. Malignant tumors can spread into, or invade, nearby tissues. They can also spread to other parts of the body through the blood and lymph systems. Also called neoplasm.
Tumor Grade
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 Marker
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).
Tumor Profiling (Gene Expression Profiling)
A laboratory method that checks for the presence of certain genes, proteins, or other molecules in a sample of blood or tumor tissue. Tumor profiling may provide information about certain molecular or genetic changes in a tumor, such as gene mutations or other changes in tumor DNA. It may be used to help plan treatment or predict whether cancer will come back or spread to other parts of the body.
Two-Step Procedure
Biopsy and further surgical treatment done at two separate times.
Tyrosine-Kinase Inhibitors
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.