Glossary

We have gathered terms and definitions related to cancer and medicine on this page. Sources for definitions include the American Cancer Society and National Cancer Institute.

Allogeneic stem cell transplant

Uses bone marrow or stem cells from a donor whose tissue type closely matches the patient’s to replace blood-forming cells that have been destroyed by disease or cancer treatment. This can be from a related or unrelated donor.

Anemia

A condition in which the number of red blood cells is below normal.

Anesthesia

A loss of feeling or awareness caused by drugs or other substances. Anesthesia keeps patients from feeling pain during surgery or other procedures. Local anesthesia is a loss of feeling in one small area of the body, such as the mouth. Regional anesthesia is a loss of feeling in a part of the body, such as an arm or leg. General anesthesia is a loss of feeling and a complete loss of awareness that feels like a very deep sleep.

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.

Antibody

A protein made by immune system cells and released into the blood. Antibodies defend the body against foreign substances, such as bacteria.

Antibody therapy

A 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.

Antigen

A foreign substance, such as bacteria, that causes the body’s immune system to respond by making antibodies. Antibodies defend the body against antigens.

Apheresis

A procedure in which blood is taken out of the body, part of the blood is removed, and the rest of the blood is infused back into the body.

Autologous bone marrow transplant

A procedure in which a patient’s healthy stem cells (blood-forming cells) are collected from the bone marrow before treatment, stored and then given back to the patient after treatment. An autologous bone marrow transplant replaces a patient’s stem cells that have been destroyed by treatment with radiation or high doses of chemotherapy.

B cell

A type of white blood cell that makes antibodies. B cells are part of the immune system and develop from stem cells in the bone marrow.

B symptoms

In lymphoma, B symptoms include unexplained fever, weight loss or night sweats.

B-cell lymphoma

A type of cancer that forms in B cells (a type of immune system cell). B-cell lymphomas may be either indolent (slow-growing) or aggressive (fast-growing). Most B-cell lymphomas are non-Hodgkin lymphomas. There are many different types of B-cell non-Hodgkin lymphomas. These include Burkitt lymphoma, chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), diffuse large B-cell lymphoma, follicular lymphoma and mantle cell lymphoma. Prognosis and treatment depend on the type and stage of the cancer.

Benign

Not cancer. Benign tumors may grow larger but do not spread to other parts of the body.

Benign prostatic hyperplasia

A benign (not cancer) condition in which an overgrowth of prostate tissue pushes against the urethra and the bladder, blocking the flow of urine. Also called benign prostatic hypertrophy and BPH.

Beta-2 microglobulin

A small protein normally found on the surface of many cells, including lymphocytes, and in small amounts in the blood and urine. An increased amount in the blood or urine may be a sign of certain diseases, including some types of cancer, such as multiple myeloma or lymphoma.

Biopsy

The removal of a sample of tissue or fluid that is examined to see whether cancer is present. This may be done with a large needle or through surgical removal of tissue or fluids.

Blood chemistry test

A test done on a sample of blood to measure the amount of certain substances in the body. These substances include electrolytes (such as sodium, potassium and chloride), fats, proteins, glucose (sugar) and enzymes. Blood chemistry tests give important information about how well a person’s kidneys, liver and other organs are working. An abnormal amount of a substance in the blood can be a sign of disease or a side effect of treatment. Blood chemistry tests are used to help diagnose and monitor many conditions before, during and after treatment.

Blood transfusion

A procedure in which whole blood, or parts of the blood, are put into a patient’s bloodstream through a vein. The blood may be donated by another person, or it may have been taken from the patient and stored until needed. Also called transfusion.

Bone marrow

The soft, spongy material in the center of your bones that produces all your blood cells, such as white blood cells, red blood cells and platelets.

Bone marrow transplant

The process of treating disease with high doses of chemotherapy, radiation therapy or both. Because this treatment destroys the bone marrow’s ability to produce blood cells, bone marrow or peripheral blood stem cells are given after treatment to help the body make more blood cells.

Bone scan

A procedure to check for abnormal areas or damage in the bones. A very small amount of radioactive material is injected into a vein and travels through the blood. The radioactive material collects in the bones and is detected by a scanner (a special camera that takes pictures of the inside of the body). A bone scan may be used to diagnose bone tumors or cancer that has spread to the bone. It may also be used to help diagnose fractures, bone infections or other bone problems. [removed comma]

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.

Caregiver

A person who gives care to people who need help taking care of themselves, such as children, older people or patients who have chronic illnesses or disabilities. Caregivers may be health professionals, family members, friends, social workers or members of the clergy. They may give care at home, in a hospital or in another health care setting.

Central venous catheter

A small, flexible tube inserted into a large vein near the heart. This serves as a route for medications and intravenous nutrition and to take blood samples. These catheters are also known as a Hickman line, central line, tunneled catheter or Port-a-Cath®.

Chemoprevention

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

Anesthesia Drugs or other substances that cause a loss of feeling or awareness. This keeps patients from feeling pain during surgery or other procedures. A loss of feeling or awareness caused by drugs or other substances. Anesthesia keeps patients from feeling pain during surgery or other procedures. Local anesthesia is a loss of feeling in one small area of the body, such as the mouth. Regional anesthesia is a loss of feeling in a part of the body, such as an arm or leg. General anesthesia is a loss of feeling and a complete loss of awareness that feels like a very deep sleep. Antibody A protein made by immune system cells and released into the blood. Antibodies defend the body against foreign substances, such as bacteria. Antibody A protein made by immune system cells and released into the blood. Antibodies defend the body against foreign substances, such as bacteria. Autologous bone marrow transplant A procedure in which a patient’s healthy stem cells (blood-forming cells) are collected from the bone marrow before treatment, stored and then given back to the patient after treatment. A procedure in which a patient’s healthy stem cells (blood-forming cells) are collected from the bone marrow before treatment, stored and then given back to the patient after treatment. An autologous bone marrow transplant replaces a patient’s stem cells that have been destroyed by treatment with radiation or high doses of chemotherapy. B cell A type of white blood cell that makes antibodies. B cells are part of the immune system and develop from stem cells in the bone marrow. B-cell lymphoma A type of cancer that forms in B cells (a type of immune system cell). B-cell lymphomas may be either indolent (slow-growing) or aggressive (fast-growing). Most B-cell lymphomas are non-Hodgkin lymphomas. A type of cancer that forms in B cells (a type of immune system cell). B-cell lymphomas may be either indolent (slow-growing) or aggressive (fast-growing). Most B-cell lymphomas are non-Hodgkin lymphomas. There are many different types of B-cell non-Hodgkin lymphomas. These include Burkitt lymphoma, chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), diffuse large B-cell lymphoma, follicular lymphoma and mantle cell lymphoma. Prognosis and treatment depend on the type and stage of the cancer. B symptoms In lymphoma, B symptoms include unexplained fever, weight loss or night sweats. Benign Not cancer. Benign tumors may grow larger but do not spread to other parts of the body. Benign prostatic hyperplasia A benign (not cancer) condition in which an overgrowth of prostate tissue pushes against the urethra and the bladder, blocking the flow of urine. Also called benign prostatic hypertrophy and BPH. Benign prostatic hyperplasia A benign (not cancer) condition in which an overgrowth of prostate tissue pushes against the urethra and the bladder, blocking the flow of urine. Also called benign prostatic hypertrophy and BPH. Blood chemistry test A test done on a sample of blood to measure the amount of certain substances in the body. An abnormal amount of a substance in the blood can be a sign of disease or a side effect of treatment. A test done on a sample of blood to measure the amount of certain substances in the body. These substances include electrolytes (such as sodium, potassium and chloride), fats, proteins, glucose (sugar) and enzymes. Blood chemistry tests give important information about how well a person’s kidneys, liver and other organs are working. An abnormal amount of a substance in the blood can be a sign of disease or a side effect of treatment. Blood chemistry tests are used to help diagnose and monitor many conditions before, during and after treatment. Blood transfusion A procedure in which whole blood, or parts of the blood, are put into a patient’s bloodstream through a vein. The blood may be donated by another person, or it may have been taken from the patient. A procedure in which whole blood, or parts of the blood, are put into a patient’s bloodstream through a vein. The blood may be donated by another person, or it may have been taken from the patient and stored until needed. Also called transfusion. Bone marrow The soft, spongy material in the center of your bones that produces all your blood cells, such as white blood cells, red blood cells and platelets. Bone scan A procedure to check for abnormal areas or damage in the bones. A bone scan may be used to diagnose bone tumors or cancer that has spread to the bone. A procedure to check for abnormal areas or damage in the bones. A very small amount of radioactive material is injected into a vein and travels through the blood. The radioactive material collects in the bones and is detected by a scanner (a special camera that takes pictures of the inside of the body). A bone scan may be used to diagnose bone tumors or cancer that has spread to the bone. It may also be used to help diagnose fractures, bone infections or other bone problems. [removed comma] Bronchoscopy A procedure to examine the inside of the trachea, bronchi (air passages that lead to the lungs) and lungs. Uses a thin, tube-like instrument called a bronchoscope. 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. Central venous catheter A small, flexible tube inserted into a large vein near the heart. This serves as a route for medications and intravenous nutrition and to take blood samples. A small, flexible tube inserted into a large vein near the heart. This serves as a route for medications and intravenous nutrition and to take blood samples. These catheters are also known as a Hickman line, central line, tunneled catheter or Port-a-Cath®. Central venous catheter A small, flexible tube inserted into a large vein near the heart. This serves as a route for medications and intravenous nutrition and to take blood samples. A small, flexible tube inserted into a large vein near the heart. This serves as a route for medications and intravenous nutrition and to take blood samples. These catheters are also known as a Hickman line, central line, tunneled catheter or Port-a-Cath®. Central venous catheter A small, flexible tube inserted into a large vein near the heart. This serves as a route for medications and intravenous nutrition and to take blood samples. A small, flexible tube inserted into a large vein near the heart. This serves as a route for medications and intravenous nutrition and to take blood samples. These catheters are also known as a Hickman line, central line, tunneled catheter or Port-a-Cath®. Central venous catheter A small, flexible tube inserted into a large vein near the heart. This serves as a route for medications and intravenous nutrition and to take blood samples. A small, flexible tube inserted into a large vein near the heart. This serves as a route for medications and intravenous nutrition and to take blood samples. These catheters are also known as a Hickman line, central line, tunneled catheter or Port-a-Cath®. Chemotherapy Treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. It may be given alone or with other treatments. Treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. Chemotherapy may be given by mouth, injection, infusion or on the skin, depending on the type and stage of the cancer being treated. It may be given alone or with other treatments, such as surgery, radiation therapy or biologic therapy. Follicular lymphoma A type of B-cell non-Hodgkin lymphoma (cancer of the immune system) that is usually indolent (slow-growing). The tumor cells grow as groups to form nodules. A type of B-cell non-Hodgkin lymphoma (cancer of the immune system) that is usually indolent (slow-growing). The tumor cells grow as groups to form nodules. There are several subtypes of follicular lymphoma. Indolent Slow-growing. Lymphocyte A type of immune cell that is made in the bone marrow and is found in the blood and in lymph tissue. The two main types of lymphocytes are B lymphocytes and T lymphocytes. A type of immune cell that is made in the bone marrow and is found in the blood and in lymph tissue. The two main types of lymphocytes (white blood cells) are B lymphocytes and T lymphocytes. B lymphocytes make antibodies, and T lymphocytes help kill tumor cells and help control immune responses. Lymphoma Cancer that begins in the cells of the immune system. There are two basic categories of lymphomas: Hodgkin lymphoma and non-Hodgkin lymphomas. Cancer that begins in cells of the immune system. There are two basic categories of lymphomas. One is Hodgkin lymphoma, which is marked by the presence of a type of cell called the Reed-Sternberg cell. The other category is non-Hodgkin lymphomas, which includes a large, diverse group of cancers of immune system cells. Non-Hodgkin 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 and non-Hodgkin lymphomas can occur in children and adults, and prognosis and treatment depend on the stage and the type of cancer. Mantle cell lymphoma An aggressive (fast-growing) type of B-cell non-Hodgkin lymphoma that usually occurs in middle-aged or older adults. An aggressive (fast-growing) type of B-cell non-Hodgkin lymphoma that usually occurs in middle-aged or older adults. It is marked by small- to medium-size cancer cells that may be in the lymph nodes, spleen, bone marrow, blood and gastrointestinal system. Nonmalignant Not cancer. Nonmalignant tumors may grow larger but do not spread to other parts of the body. Also called benign. Platelet A tiny, disc-shaped piece of a cell that is found in the blood and spleen. Platelets help form blood clots to slow or stop bleeding and to help wounds heal. A tiny, disc-shaped piece of a cell that is found in the blood and spleen. Platelets are pieces of very large cells in the bone marrow called megakaryocytes. They help form blood clots to slow or stop bleeding and to help wounds heal. Having too many or too few platelets, or having platelets that do not work as they should, can cause problems. Checking the number of platelets in the blood may help diagnose certain diseases or conditions. Prognosis A statement about the likely outcome of a disease in a patient. Radiation therapy The use of high-energy radiation from X-rays, gamma rays, neutrons, protons and other sources to kill cancer cells and shrink tumors. The use of high-energy radiation from x-rays, gamma rays, neutrons, protons and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy or brachytherapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Recurrence Cancer that has come back, usually after a period during which it could not be detected. It may come back to the same place as the original (primary) tumor or someplace else. Also called recurrent cancer. Red blood cell A type of blood cell that carries oxygen in the body. Side effects A problem that occurs when treatment affects healthy tissues or organs. Some side effects of cancer treatment are nausea, vomiting, fatigue, pain, decreased blood cell counts, hair loss and mouth sores. Sign In medicine, a sign is something found during a physical exam or from a laboratory test that shows that a person may have a condition or disease. In medicine, a sign is something found during a physical exam or from a laboratory test that shows that a person may have a condition or disease. Some examples of signs are fever, swelling, skin rash, high blood pressure and high blood glucose. Sign In medicine, a sign is something found during a physical exam or from a laboratory test that shows that a person may have a condition or disease. In medicine, a sign is something found during a physical exam or from a laboratory test that shows that a person may have a condition or disease. Some examples of signs are fever, swelling, skin rash, high blood pressure and high blood glucose. Stage The extent of a cancer in the body. Staging is usually based on the size of the tumor, whether lymph nodes contain cancer and whether the cancer has spread from the original site to other parts of the body. Stem cell A cell from which other types of cells develop. For example, blood cells develop from blood-forming stem cells. Stem cell A cell from which other types of cells develop. For example, blood cells develop from blood-forming stem cells. White blood cell A type of blood cell that is made in the bone marrow and found in the blood and lymph tissue. White blood cells are part of the body’s immune system and help the body fight infection and other diseases. A type of blood cell that is made in the bone marrow and found in the blood and lymph tissue. White blood cells are part of the body’s immune system. They help the body fight infection and other diseases. Types of white blood cells include granulocytes (neutrophils, eosinophils and basophils), monocytes and lymphocytes (T cells and B cells). Checking the number of white blood cells in the blood is usually part of a complete blood cell (CBC) test. It may be used to look for conditions such as infection, inflammation, allergies and leukemia. Also called leukocyte and WBC.