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Glossary of Terms

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

Acute myeloid leukemia (AML) - A quickly progressing disease in which too many immature white blood cells (not lymphocytes) are found in the blood and bone marrow. Also called acute myelogenous leukemia or acute nonlymphocytic leukemia.

Acute promyelocytic leukemia - A subtype of acute myeloid leukemia.

Adjuvant therapy - Treatment given after the primary treatment to increase the chances of a cure. Adjuvant therapy may include chemotherapy, radiation therapy, hormone therapy, or biological therapy.

Adrenal glands - A pair of small glands, one located on top of each kidney. They produce steroid hormones, adrenaline and noradrenaline, which help control heart rate, blood pressure, and other important body functions.

Anaplastic - A term used to describe cancer cells that divide rapidly and have no resemblance to normal cells.

Androgen suppression - Treatment to suppress or block the production of male hormones. Androgen suppression is achieved by surgical removal of the testicles, by taking female sex hormones, or by taking other drugs, antiandrogens. Also called androgen ablation.

Androgens - A family of hormones that promote the development and maintenance of male sex characteristics.

Anemia - A condition in which the number of red blood cells is below normal. This can cause tiredness, shortness of breath, chest pain.

Angiogenesis - Blood vessel formation. Tumor angiogenesis is the growth of blood vessels from surrounding tissue to a solid tumor. This is caused by the release of chemicals by the tumor.

Angiogenesis inhibitor - A substance that may prevent the formation of blood vessels. In anticancer therapy, an angiogenesis inhibitor prevents the growth of blood vessels from surrounding tissue to a solid tumor.

Anthracycline - A type of antibiotic that comes from the fungus Streptococcus peucetius. Anthracyclines are used as treatments for cancer. Daunorubicin, doxorubicin, and epirubicin are anthracyclines.

Antibody - A type of protein made by certain white blood cells in response to a foreign substance (antigen). Each antibody can bind to only a specific antigen. The purpose of this binding is to help destroy the antigen. Antibodies can work in several ways, depending on the nature of the antigen. Some antibodies destroy antigens directly. Others make it easier for white blood cells to destroy.

Antibody therapy - Treatment with an antibody, a substance that can directly kill specific tumor cells or stimulate the immune system to kill tumor cells.

Anticancer antibiotics - A group of anticancer drugs that block cell growth by interfering with DNA, the genetic material in cells. Also called antitumor antibiotics or antineoplastic antibiotics.

Anticoagulant - A drug that helps prevent blood clots from forming. Also called a blood thinner.

Antiestrogen - A substance that blocks the activity of estrogens, the family of hormones that promote the development and maintenance of female sex characteristics.

Antihormone therapy - Treatment with drugs, surgery, or radiation in order to block the production or action of a hormone. Antihormones therapy may be used in cancer treatment because certain hormones are able to stimulate the growth of some types of tumors.

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.

Antimicrotubule agent - A drug that inhibits cell growth by stopping cell division. Antimicrotubule agents are used as treatments for cancer. Also called antimitotic agents, mitotic inhibitors, and taxanes. Docetaxel and paclitaxel are antimicrotubule agents.

Antineoplastic- A substance that blocks the formation of neoplasms (growths that may become cancerous).

Antioxidant - A substance that protects cells from the damage caused by free radicals (unstable molecules made by the process of oxidation during normal metabolism). Free radicals may play a part in cancer, heart disease, stroke, and other diseases of aging. Antioxidants include beta-carotene, lycopene, vitamins A, C, and E, and other natural and manufactured substances.

Areola - The area of dark-colored skin on the breast that surrounds the nipple.

Aromatase inhibitor - A drug that prevents the formation of estradiol, a female hormone, by interfering with an aromatase enzyme. Aromatase inhibitors are used to treat a type of hormone-dependent breast cancer.

Axilla - The underarm or armpit.

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

Axillary dissection - Surgery to remove lymph nodes found in the armpit region. Also called axillary lymph node dissection.

Axillary lymph node dissection - Surgery to remove lymph nodes found in the armpit region. Also called axillary dissection.

Axillary lymph nodes - Lymph nodes found in the armpit regions that drain lymph channels from the breast.


B cell - A white blood cell that comes from bone marrow. As part of the immune system, B cells make antibodies and help fight infections. Also called B lymphocyte.

B lymphocyte - A white blood cell that comes from bone marrow. As part of the immune system, B lymphocytes make antibodies and help fight infections. Also called B cell.

B cell lymphoma - A type of cancer that forms in B cells (a type of immune system cell). B-cell lymphomas usually occur in adults and may be either indolent (slow-growing) or aggressive (fast-growing). There are many different types of B-cell lymphomas, and prognosis and treatment depend on the type and stage of cancer.

Baseline - An initial measurement that is taken at an early time point to represent a beginning condition, and is used for comparison over time to look for changes. For example, the size of a tumor will be measured before treatment (baseline) and then afterwards to see if the treatment had an effect.

Bevacizumab - A drug used to treat several types of cancer, including certain types of colorectal, lung, and breast cancers and glioblastoma. It is also being studied in the treatment of other types of cancer. Bevacizumab binds to vascular endothelial growth factor (VEGF) and may prevent the growth of new blood vessels that tumors need to grow. It is a type of antiangiogenesis agent and a type of monoclonal antibody. Also called Avastin.

Bilateral - Affecting both the right and left sides of the body.

Bilateral Cancer - Cancer that occurs in both paired organs, such as both breasts or both ovaries.

Biological therapy - Treatment to stimulate or restore the ability of the immune system to fight infections and other diseases. Also used to lessen side effects that may be caused by some cancer treatments. Also known as immunotherapy, biotherapy, or biological response modifier (BRM) therapy.

Biopsy - The removal of cells or tissues for examination under a microscope. When only a sample of tissue is removed, the procedure is called an incisional biopsy or core biopsy. When an entire lump or suspicious area is removed, the procedure is called an excisional biopsy. When a sample of tissue or fluid is removed with a needle, the procedure is called a needle biopsy or fine-needle aspiration.

Bisphosphonate- A drug or substance used to treat hypercalcemia (abnormally high blood calcium) and bone pain caused by some types of cancer. Forms of bisphosphonates are also used to treat osteoporosis and for bone imaging. Bisphosphonates inhibit a type of bone cell that breaks down bone. Also called diphosphonate.

Blinded Study - A type of study in which the patients (single-blinded) or the patients and their doctors (double-blinded) do not know which drug or treatment is being given. The opposite of a blinded study is an open label study

Blood Cell Count - A test to check the number of red blood cells, white blood cells, and platelets in a sample of blood. Also called complete blood count (CBC).

Blood Chemistry- A procedure in which a sample of blood is examined to measure the amounts of certain substances made in the body. An abnormal amount of a substance can be a sign of disease in the organ or tissue that produces it.

Bone marrow - The soft, sponge-like tissue in the center of most large bones. It produces white blood cells, red blood cells, and platelets.

Bone Scan - A technique to create images of bones on a computer screen or on film. A small amount of radioactive material is injected into a blood vessel and travels through the bloodstream; it collects in the bones and is detected by a scanner.

Brain metastasis - Cancer that has spread from the original (primary) tumor to the brain.

Brain tumor - The growth of abnormal cells in the tissues of the brain. Brain tumors can be benign (not cancer) or malignant (cancer).

Breast cancer - Cancer that forms in tissues of the breast, usually the ducts (tubes that carry milk to the nipple) and lobules (glands that make milk). It occurs in both men and women, although male breast cancer is rare.

Breast Cancer in SITU - Abnormal cells that are confined to the ducts or lobules in the breast. There are two forms, called ductal carcinoma in situ (DCIS) and lobular carcinoma in situ (LCIS).

Bronchoscopy - A procedure that uses a bronchoscope to examine the inside of the trachea, bronchi (air passages that lead to the lungs), and lungs. A bronchoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease. The bronchoscope is inserted through the nose or mouth. Bronchoscopy may be used to detect cancer or to perform some treatment procedures.


Cancer - A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread through the bloodstream and lymphatic system to other parts of the body. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the bloodstream. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system.

Carboplatin - A drug that is used to treat advanced ovarian cancer that has never been treated or symptoms of ovarian cancer that has come back after treatment with other anticancer drugs. It is also used together with other drugs to treat advanced, metastatic, or recurrent non-small cell lung cancer and is being studied in the treatment of other types of cancer. Carboplatin is a form of the anticancer drug cisplatin and causes fewer side effects in patients. It attaches to DNA in cells and may kill cancer cells. It is a type of platinum compound. Also called Paraplatin.

Cell - The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

Chemoprevention - The use of drugs, vitamins, or other agents to try to reduce the risk of, or delay the development or recurrence of cancer.

Chemoradiation- Treatment that combines chemotherapy with radiation therapy. Also called chemoradiotherapy

Chemotherapy - Treatment with anticancer drugs.

Chronic lymphocytic leukemia (CLL)- A slowly progressing disease in which too many white blood cells (called lymphocytes) are found in the body.

Cisplatin - A drug used to treat many types of cancer. Cisplatin contains the metal platinum. It kills cancer cells by damaging their DNA and stopping them from dividing. Cisplatin is a type of alkylating agent. Also called Platinol.

Clinical Study - A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called a clinical trial.

CNS - Central nervous system. The brain and spinal cord. Also called central nervous system.

CNS metastasis - Central nervous system metastasis. Cancer that has spread from the original (primary) tumor to the central nervous system (CNS). Also called central nervous system metastasis.

Colony stimulating factors - Substances that stimulate the production of blood cells. Colony-stimulating factors include granulocyte colony-stimulating factors (also called G-CSF and filgrastim), granulocyte-macrophage colony-stimulating factors (also called GM-CSF and sargramostim), and promegapoietin.

Colorectal Cancer - Cancer that develops in the colon (the longest part of the large intestine) and/or the rectum (the last several inches of the large intestine before the anus).

Continuous infusions - The administration of a fluid into a blood vessel, usually over a prolonged period of time.

Combination chemotherapy - Treatment using more than one anticancer drug.

Corticosteroids - Hormones that have antitumor activity in lymphomas and lymphoid leukemias; in addition, corticosteroids (steroids) may be used for hormone replacement and for the management of some of the complications of cancer and its treatment.

Cryosurgery - Treatment performed with an instrument that freezes and destroys abnormal tissues.

Cytologically - Having to do with the cells. Examining cells under a microscope to determine if they are normal cells or cancer cells.


DCIS - Ductal carcinoma in situ. A noninvasive condition in which abnormal cells are found in the lining of a breast duct. The abnormal cells have not spread outside the duct to other tissues in the breast. In some cases, DCIS may become invasive cancer and spread to other tissues, although it is not known at this time how to predict which lesions will become invasive. Also called intraductal carcinoma.

Distant metastasis - Refers to cancer that has spread from the original (primary) tumor to distant organs or distant lymph nodes. Also known as distant cancer.

Double blinded - A clinical trial in which neither the medical staff nor the person knows which of several possible therapies the person is receiving.

Drug - Any substance, other than food, that is used to prevent, diagnose, treat or relieve symptoms of a disease or abnormal condition. Also refers to a substance that alters mood or body function, or that can be habit-forming or addictive, especially a narcotic.


Eligibility Criteria - In clinical trials, requirements that must be met for an individual to be included in a study. These requirements help make sure that patients in a trial are similar to each other in terms of specific factors such as age, type and stage of cancer, general health, and previous treatment. When all participants meet the same eligibility criteria, it gives researchers greater confidence that results of the study are caused by the intervention being tested and not by other factors.

Enzymes - A protein that speeds up chemical reactions in the body.

Estrogen - Hormones that promote the development and maintenance of female sex characteristics.

Estrogen receptor negative - ER-. Describes cells that do not have a protein to which the hormone estrogen will bind. Cancer cells that are ER- do not need estrogen to grow, and usually do not stop growing when treated with hormones that block estrogen from binding.

Estrogen receptor positive - ER+. Describes cells that have a protein to which the hormone estrogen will bind. Cancer cells that are ER+ need estrogen to grow, and may stop growing when treated with hormones that block estrogen from binding.

Extensive stage small cell lung cancer - Cancer that has spread outside the lung to other tissues in the chest or to other parts of the body.


Fallopian tube - A slender tube through which eggs pass from an ovary to the uterus. In the female reproductive tract, there is one ovary and one fallopian tube on each side of the uterus.

Familial cancer- Cancer that occurs in families more often than would be expected by chance. These cancers often occur at an early age, and may indicate the presence of a gene mutation that increases the risk of cancer. They may also be a sign of shared environmental or lifestyle factors.

Family History - A record of a person's current and past illnesses, and those of his or her parents, brothers, sisters, children, and other family members. A family history shows the pattern of certain diseases in a family, and helps to determine risk factors for those and other diseases.


Gastrointestinal stromal tumor - GIST. A type of tumor that usually begins in cells in the wall of the gastrointestinal tract. It can be benign or malignant.

Genetic Counseling - A communication process between a specially trained health professional and a person concerned about the genetic risk of disease. The person's family and personal medical history may be discussed, and counseling may lead to genetic testing.


HER 2 - Human epidermal growth factor receptor 2. The HER2/neu protein is involved in the growth of some cancer cells. Also called c-erbB-2.

High-risk cancer - Cancer that is likely to recur (come back), or spread.

Histology - The study of tissue sectioned as a thin slice, using a microtome. It can be described as microscopic anatomy. Histology is an essential tool of biology.

Hormone therapy- Treatment with hormones to replace or block other hormones. For certain conditions (such as diabetes or menopause), hormones are given to adjust low hormone levels. To slow or stop the growth of certain cancers (such as prostate and breast cancer), hormones may be given to block the body's natural hormones. Also called hormonal therapy, hormone treatment, or endocrine therapy.

Hormone receptor - A protein on the surface of a cell that binds to a specific hormone. The hormone causes many changes to take place in the cell.

Hormones - Chemicals made by glands in the body. Hormones circulate in the bloodstream and control the actions of certain cells or organs. Some hormones can also be made in a laboratory.


Immune response- The activity of the immune system against foreign substances (antigens).

Inflammatory breast cancer - A type of breast cancer in which the breast looks red and swollen and feels warm. The skin of the breast may also show the pitted appearance called peau d'orange (like the skin of an orange). The redness and warmth occur because the cancer cells block the lymph vessels in the skin.

Infusions - A method of putting fluids, including drugs, into the bloodstream. Also called intravenous infusion.

Intraperitoneal chemotherapy - Treatment in which anticancer drugs are put directly into the abdominal cavity through a thin tube.

Intraperitoneal infusion - A method of delivering fluids and drugs directly into the abdominal cavity through a thin tube. Also called peritoneal infusion.

Intravenous - Into or within a vein. Intravenous usually refers to a way of giving a drug or other substance through a needle or tube inserted into a vein. Also called IV.


Kidney Cancer - Cancer that forms in tissues of the kidneys. Kidney cancer includes renal cell carcinoma (cancer that forms in the lining of very small tubes in the kidney that filter the blood and remove waste products) and renal pelvis carcinoma (cancer that forms in the center of the kidney where urine collects). It also includes Wilms' tumor, which is a type of kidney cancer that usually develops in children under the age of 5.


Laboratory study - Research done in a laboratory. These studies may use test tubes or animals to find out if a drug, procedure, or treatment is likely to be useful. Laboratory studies take place before any testing is done in humans.

Large cell carcinoma - Lung cancer in which the cells are large and look abnormal when viewed under a microscope.

LCIS - Lobular carcinoma in situ. Abnormal cells found in the lobules of the breast. This condition seldom becomes invasive cancer; however, having lobular carcinoma in situ increases one's risk of developing breast cancer in either breast.

Letrozole - A drug used to treat advanced breast cancer in postmenopausal women. Letrozole causes a decrease in the amount of estrogen made by the body. It is a type of aromatase inhibitor. Also called Femara.

Limited stage small-cell lung cancer - Cancer found in one lung and in nearby lymph nodes.

Locally advanced - Cancer that has spread only to nearby tissues or lymph nodes.

Lumpectomy - Surgery to remove the tumor and a small amount of normal tissue around it.

Lung Cancer - Cancer that forms in tissues of the lung, usually in the cells lining air passages. The two main types are small cell lung cancer and non-small cell lung cancer. These types are diagnosed based on how the cells look under a microscope.

Lymphoma - Cancer that begins in cells of the immune system. There are two basic categories of lymphomas. One kind is Hodgkin's lymphoma, which is marked by the presence of a type of cell called the Reed-Sternberg cell. The other category is non-Hodgkin's lymphomas, which includes a large, diverse group of cancers of immune system cells. Non-Hodgkin's lymphomas can be further divided into cancers that have an indolent (slow-growing) course and those that have an aggressive (fast-growing) course. These subtypes behave and respond to treatment differently. Both Hodgkin's and non-Hodgkin's lymphomas can occur in children and adults, and prognosis and treatment depend on the stage and the type of cancer.

Lymph node-positive - Cancer that has spread to the lymph nodes.

Lymph node-negative - Cancer that has not spread to the lymph nodes.


Mammography - The use of x-rays to create a picture of the breast.

Mastectomy - Surgery to remove the breast (or as much of the breast tissue as possible).

Mediastinoscopy - A procedure in which a mediastinoscope is used to examine the organs in the area between the lungs and nearby lymph nodes. A mediastinoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease The mediastinoscope is inserted into the chest through an incision above the breastbone. This procedure is usually done to get a tissue sample from the lymph nodes on the right side of the chest.

Mediastinum - The area between the lungs. The organs in this area include the heart and its large blood vessels, the trachea, the esophagus, the bronchi, and lymph nodes.

Melanoma - A form of skin cancer that arises in melanocytes, the cells that produce pigment. Melanoma usually begins in a mole.

Metastatic - Having to do with metastasis, which is the spread of cancer from one part of the body to another.

Monoclonal antibodies - Laboratory-produced substances that can locate and bind to cancer cells wherever they are in the body. Many monoclonal antibodies are used in cancer detection or therapy; each one recognizes a different protein on certain cancer cells. Monoclonal antibodies can be used alone, or they can be used to deliver drugs, toxins, or radioactive material directly to a tumor.


Needle Biopsy - The removal of tissue or fluid with a needle for examination under a microscope. Also called fine-needle aspiration.

Nephrectomy - Surgery to remove a kidney or part of a kidney. In a partial nephrectomy, part of one kidney or a tumor is removed, but not an entire kidney. In a simple nephrectomy, one kidney is removed. In a radical nephrectomy, an entire kidney, nearby adrenal gland and lymph nodes, and other surrounding tissue are removed. In a bilateral nephrectomy, both kidneys are removed.

Node negative - Cancer that has not spread to the lymph nodes.

Node positive - Cancer that has spread to the lymph nodes.

Non Hodgkins Lymphoma - NHL. Any of a large group of cancers of the immune system. NHLs can occur at any age, and are often marked by enlarged lymph nodes, fever, and weight loss. There are many different types of NHL, and they can be divided into aggressive (fast-growing) and indolent (slow-growing) types, and are classified as either B-cell or T-cell NHL. B-cell NHLs include Burkitt's lymphoma, diffuse large B-cell lymphoma, follicular lymphoma, immunoblastic large cell lymphoma, precursor B-lymphoblastic lymphoma, and mantle cell lymphoma. T-cell NHLs include mycosis fungoides, anaplastic large cell lymphoma, and precursor T-lymphoblastic lymphoma. Lymphomas related to lymphoproliferative disorders following bone marrow or stem cell transplantation are usually B-cell NHLs. Prognosis and treatment depend on the stage and type of disease.

Non-small cell lung cancer- A group of lung cancers that includes squamous cell carcinoma, adenocarcinoma, and large cell carcinoma.


Oat cell cancer - An aggressive (fast-growing) cancer that usually forms in tissues of the lung and spreads to other parts of the body. The cancer cells look small and oval-shaped when looked at under a microscope. Also called small cell lung cancer.

Observation - Closely monitoring a patient's condition but withholding treatment until symptoms appear or change. Also called watchful waiting.

Observational study - A type of study in which individuals are observed or certain outcomes are measured. No attempt is made to affect the outcome (for example, no treatment is given).

Oncotype DX - a clinically validated laboratory test, ordered by physicians, that predicts the likelihood of breast cancer recurrence in women with newly diagnosed, early stage invasive breast cancer. Oncotype DX also assesses the benefit from certain types of chemotherapy.

Open biopsy - A procedure in which a surgical incision (cut) is made through the skin to expose and remove tissues. The biopsy tissue is examined under a microscope by a pathologist. An open biopsy may be done in the doctor's office or in the hospital, and may use local anesthesia or general anesthesia. A lumpectomy to remove a breast tumor is a type of open biopsy.

Ovary - One of a pair of female reproductive glands in which the ova, or eggs, are formed. The ovaries are located in the pelvis, one on each side of the uterus.

Ovarian epithelial cancer (oh-VAYR-ee-un eh-pih-THEE-lee-ul KAN-ser) - Cancer that occurs in the cells on the surface of the ovary. Also called epithelial ovarian cancer.

Ovarian function suppression - Surgery, radiation therapy, or a drug treatment to stop the functioning of the ovaries. Also called ovarian ablation.


Paclitaxel - A drug used to treat breast cancer, ovarian cancer, and AIDS-related Kaposi sarcoma. It is also used together with another drug to treat non-small cell lung cancer. Paclitaxel is also being studied in the treatment of other types of cancer. It blocks cell growth by stopping cell division and may kill cancer cells. It is a type of antimitotic agent. Also called Taxol.

Pancreatic cancer - A disease in which malignant (cancer) cells are found in the tissues of the pancreas. Also called exocrine cancer.

Pelvis - The lower part of the abdomen, located between the hip bones.

Peripheral blood - Blood circulating throughout the body.

Peritoneal cancer - Cancer of the tissue that lines the abdominal wall and covers organs in the abdomen

Phase I - a study that is testing the best way to give a new treatment and also collects information about the safety of the drug. Small numbers of patients take part in these studies.

Phase II - A study that focuses on whether the new treatment has an anticancer effect. Small numbers of patients take part in these studies.

Phase III - A study that compares results of people taking the new treatment with results of people taking standard treatment. Large numbers of patients take part in these studies.

Placebo - An inactive substance that looks the same as, and is administered in the same way as, a drug in a clinical trial.

Post menopausal- Refers to the time after menopause. Menopause is the time in a woman's life when menstrual periods stop permanently; also called "change of life."

Primary tumor - The original tumor.

Progesterone receptor - PR. A protein found inside the cells of the female reproductive tissue, some other types of tissue, and some cancer cells. The hormone progesterone will bind to the receptors inside the cells and may cause the cells to grow.


Quality of Life - The overall enjoyment of life. Many clinical trials assess the effects of cancer and its treatment on the quality of life. These studies measure aspects of an individual's sense of well-being and ability to carry out various tasks.


Radiation therapy - The use of high-energy radiation from x-rays, gamma rays, neutrons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or from materials called radioisotopes. Radioisotopes produce radiation and can be placed in or near the tumor or in the area near cancer cells. This type of radiation treatment is called internal radiation therapy, implant radiation, interstitial radiation, or brachytherapy. Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that circulates throughout the body. Also called radiotherapy, irradiation, and x-ray therapy.

Randomization - Study participants are assigned to groups in such a way that each has an equal opportunity of being assigned to each treatment, like the flip of a coin.

Randomized clinical trial - A study in which the participants are assigned by chance to separate groups that compare different treatments; neither the researchers nor the participants can choose which group. Using chance to assign people to groups means that the groups will be similar and that the treatments they receive can be compared objectively. At the time of the trial, it is not known which treatment is best. It is the patient's choice to be in a randomized trial.

Recurrence - The return of cancer, at the same site as the original (primary) tumor or in another location, after the tumor had disappeared.

Red blood cells - RBC. A cell that carries oxygen to all parts of the body. Also called an erythrocyte.

Regimen - A treatment plan that specifies the dosage, the schedule, and the duration of treatment.


Schedule - In clinical trials, the step-by-step plan for how patients are to be treated; for example, the drug or type of radiation therapy that is to be given, the method by which it is to be given, the amount of time between courses, and the total length of treatment.

Sentinel lymph node - The first lymph node to which cancer is likely to spread from the primary tumor. Cancer cells may appear first in the sentinel node before spreading to other lymph nodes.

Sentinel lymph node biopsy - Removal and examination of the sentinel node(s) (the first lymph node(s) to which cancer cells are likely to spread from a primary tumor). To identify the sentinel lymph node(s), the surgeon injects a radioactive substance, blue dye, or both near the tumor. The surgeon then uses a scanner to find the sentinel lymph node(s) containing the radioactive substance or looks for the lymph node(s) stained with dye. The surgeon then removes the sentinel node(s) to check for the presence of cancer cells.

Stages of Cancer - the extent of a cancer and whether the disease has spread from the original site to other parts of the body.

Standard of Care - In medicine, treatment that experts agree is appropriate, accepted, and widely used. Health care providers are obligated to provide patients with the standard of care. Also called standard therapy or best practice.

Surgery - A procedure to remove or repair a part of the body or to find out whether disease is present. An operation.

Symptom management - Care given to improve the quality of life of patients who have a serious or life-threatening disease. The goal of symptom management is to prevent or treat as early as possible the symptoms of the disease, side effects caused by treatment of the disease, and psychological, social, and spiritual problems related to the disease or its treatment. Also called palliative care, comfort care, and supportive care.

Systemic therapy - Treatment using substances that travel through the bloodstream, reaching and affecting cells all over the body.


Tamoxifen - A drug used to treat certain types of breast cancer in women and men. It is also used to prevent breast cancer in women who have had ductal carcinoma in situ (abnormal cells in the ducts of the breast) and in women who are at a high risk of developing breast cancer. Tamoxifen is also being studied in the treatment of other types of cancer. It blocks the effects of the hormone estrogen in the breast. Tamoxifen is a type of antiestrogen. Also called tamoxifen citrate.

Testicles - The two egg-shaped glands found inside the scrotum. They produce sperm and male hormones. Also called testes.

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

Trastuzumab - A monoclonal antibody that binds to HER2 (human epidermal growth factor receptor 2), and can kill HER2-positive cancer cells. Monoclonal antibodies are made in the laboratory and can locate and bind to substances in the body, including cancer cells. Trastuzumab is used to treat breast cancer that is HER2-positive and has spread after treatment with other drugs. It is also used with other anticancer drugs to treat HER2-positive breast cancer after surgery. Trastuzumab is also being studied in the treatment of other types of cancer. Also called Herceptin

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 cancerous), or malignant (cancerous). Also called neoplasm.

Tyrosine kinase inhibitor - A drug that interferes with cell communication and growth and may prevent tumor growth. Some tyrosine kinase inhibitors are used to treat cancer.


Unresectable - Unable to be removed with surgery.


Vaccines - A substance or group of substances meant to cause the immune system to respond to a tumor or to microorganisms, such as bacteria or viruses. A vaccine can help the body recognize and destroy cancer cells or microorganisms.

VEGF - Vascular endothelial growth factor. A substance made by cells that stimulates new blood vessel formation.

Vitamin E - A substance used in cancer prevention. It belongs to the family of drugs called tocopherols.


Watchful waiting - Closely monitoring a patient's condition but withholding treatment until symptoms appear or change. Also called observation.

White blood cells - WBC. Refers to a blood cell that does not contain hemoglobin. White blood cells include lymphocytes, neutrophils, eosinophils, macrophages, and mast cells. These cells are made by bone marrow and help the body fight infection and other diseases.


X-ray - A type of high-energy radiation. In low doses, X-rays are used to diagnose diseases by making pictures of the inside of the body. In high doses, X-rays are used to treat cancer.

Last Updated: 6/11/2012