Glossary Terms

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

Not normal. An abnormal lesion or growth may be cancer, premalignant (likely to become cancer), or benign (not cancer).

A disease caused by the human immunodeficiency virus (HIV). People with AIDS are at an increased risk for developing certain cancers and for infections that usually occur only in individuals with a weak immune system. Also called acquired immunodeficiency syndrome.

A soft tissue tumor that is most common in older children and teenagers. It begins in the soft supporting tissue that connects and surrounds the organs and other tissues. Alveolar soft part sarcoma usually occurs in the legs, but can also occur in the arms, hands, head, or neck. It can cause the growth of new blood vessels that help the tumor grow and spread. Also called ASPS.

A benign (noncancer) tumor of fat and muscle tissue that usually is found in the kidney. Angiomyolipomas rarely cause symptoms, but may bleed or grow large enough to be painful or cause kidney failure. They are common in patients with tuberous sclerosis (a genetic disorder in which benign tumors grow in the kidneys, brain, eyes, heart, lungs, and skin, causing seizures, mental problems, and skin lesions).

A type of cancer that begins in the cells that line blood vessels or lymph vessels. Cancer that begins in blood vessels is called hemangiosarcoma. Cancer that begins in lymph vessels is called lymphangiosarcoma.

Any substance that causes the body to make a specific immune response.

The removal of cells or tissues for examination by a pathologist. The pathologist may study the tissue under a microscope or perform other tests on the cells or tissue. There are many different types of biopsy procedures. The most common types include: (1) incisional biopsy, in which only a sample of tissue is removed; (2) excisional biopsy, in which an entire lump or suspicious area is removed; and (3) needle biopsy, in which a sample of tissue or fluid is removed with a needle. When a wide needle is used, the procedure is called a core biopsy. When a thin needle is used, the procedure is called a fine-needle aspiration biopsy.

A tissue with red blood cells, white blood cells, platelets, and other substances suspended in fluid called plasma. Blood takes oxygen and nutrients to the tissues, and carries away wastes.

A tube through which the blood circulates in the body. Blood vessels include a network of arteries, arterioles, capillaries, venules, and veins.

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

A term for diseases in which abnormal cells divide without control and can invade nearby tissues. Cancer cells can also spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is a cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is a cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is a 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 blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord. Also called malignancy.

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

A type of cancer that forms in bone cartilage. It usually starts in the pelvis (between the hip bones), the shoulder, the ribs, or at the ends of the long bones of the arms and legs. A rare type of chondrosarcoma called extraskeletal chondrosarcoma does not form in bone cartilage. Instead, it forms in the soft tissues of the upper part of the arms and legs. Chondrosarcoma can occur at any age but is more common in people older than 40 years. It is a type of bone cancer.

Part of a cell that contains genetic information. Except for sperm and eggs, all human cells contain 46 chromosomes.

A type of cell that looks clear inside when viewed under a microscope.

A soft tissue tumor that begins in a tendon (tough, fibrous, cord-like tissue that connects muscle to bone or to another structure). Clear cell sarcoma of soft tissue has certain markers that are also found on malignant melanoma (a type of skin cancer). It usually occurs in the leg or arm. Also called malignant melanoma of soft parts.

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 clinical study.

In medicine, a health problem with certain characteristics or symptoms.

Supporting tissue that surrounds other tissues and organs. Specialized connective tissue includes bone, cartilage, blood, and fat.

The removal of a tissue sample with a wide needle for examination under a microscope. Also called core needle biopsy.

A series of detailed pictures of areas inside the body taken from different angles. The pictures are created by a computer linked to an x-ray machine. Also called CAT scan, computed tomography scan, computerized axial tomography scan, and computerized tomography.

The study of chromosomes and chromosomal abnormalities.

A type of tumor that begins as a hard nodule and grows slowly. These tumors are usually found in the dermis (the inner layer of the two main layers of tissue that make up the skin) of the limbs or trunk of the body. They can grow into surrounding tissue but do not spread to other parts of the body. These tumors are related to giant cell fibroblastomas.

A tumor of the tissue that surrounds muscles, usually in the abdomen. A desmoid tumor rarely metastasizes (spreads to other parts of the body). It may be called aggressive fibromatosis when the tumor is outside of the abdomen.

A rare, aggressive cancer that usually affects young males and usually is located in the abdomen.

The process of identifying a disease, such as cancer, from its signs and symptoms.

In medicine, a disturbance of normal functioning of the mind or body. Disorders may be caused by genetic factors, disease, or trauma.

A microscope (device used to magnify small objects) that uses electrons (instead of light) to produce an enlarged image. An electron microscope shows tiny details better than any other type of microscope.

A protein that speeds up chemical reactions in the body.

A common virus that remains dormant in most people. It causes infectious mononucleosis and has been associated with certain cancers, including Burkitt lymphoma, immunoblastic lymphoma, and nasopharyngeal carcinoma. Also called EBV.

A surgical procedure in which an entire lump or suspicious area is removed for diagnosis. The tissue is then examined under a microscope.

Located outside of the bone.

An inherited condition in which numerous polyps (growths that protrude from mucous membranes) form on the inside walls of the colon and rectum. It increases the risk of colorectal cancer. Also called familial polyposis and FAP.

A type of soft tissue sarcoma that begins in fibrous tissue, which holds bones, muscles, and other organs in place.

The removal of tissue or fluid with a thin needle for examination under a microscope. Also called FNA biopsy.

A substance that flows smoothly and takes the shape of its container. Liquids and gases are fluids.

A description of a tumor based on how abnormal the cancer cells look under a microscope and how quickly the tumor is likely to grow and spread. Grading systems are different for each type of cancer.

A type of cancer involving blood vessels and soft tissue.

A term used to describe cells that look abnormal under a microscope. These cells are more likely to grow and spread quickly than cells in low-grade cancer or in growths that may become cancer.

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

A technique used to identify specific molecules in different kinds of tissue. The tissue is treated with antibodies that bind the specific molecule. These are made visible under a microscope by using a color reaction, a radioisotope, colloidal gold, or a fluorescent dye. Immunohistochemistry is used to help diagnose diseases, such as cancer, and to detect the presence of microorganisms. It is also used in basic research to understand how cells grow and differentiate (become more specialized).

A surgical procedure in which a portion of a lump or suspicious area is removed for diagnosis. The tissue is then examined under a microscope to check for signs of disease.

Invasion and multiplication of germs in the body. Infections can occur in any part of the body and can spread throughout the body. The germs may be bacteria, viruses, yeast, or fungi. They can cause a fever and other problems, depending on where the infection occurs. When the body’s natural defense system is strong, it can often fight the germs and prevent infection. Some cancer treatments can weaken the natural defense system.

Transmitted through genes that have been passed from parents to their offspring (children).

In medicine, the place where two or more bones are connected. Examples include the shoulder, elbow, knee, and jaw.

A medical procedure that involves testing a sample of blood, urine, or other substance from the body. Tests can help determine a diagnosis, plan treatment, check to see if treatment is working, or monitor the disease over time.

A malignant (cancer) tumor of smooth muscle cells that can arise almost anywhere in the body, but is most common in the uterus, abdomen, or pelvis.

A rare, inherited predisposition to multiple cancers, caused by an alteration in the p53 tumor suppressor gene.

A rare cancer of the fat cells.

A term used to describe cells that look nearly normal under a microscope. These cells are less likely to grow and spread more quickly than cells in high-grade cancer or in growths that may become cancer.

A rounded mass of lymphatic tissue that is surrounded by a capsule of connective tissue. Lymph nodes filter lymph (lymphatic fluid), and they store lymphocytes (white blood cells). They are located along lymphatic vessels. Also called lymph gland.

A thin tube that carries lymph (lymphatic fluid) and white blood cells through the lymphatic system. Also called lymphatic vessel.

A type of cancer that begins in the cells that line lymph vessels.

Cancerous. Malignant cells can invade and destroy nearby tissue and spread to other parts of the body.

A rare, fast-growing tumor of the nervous system or soft tissue that occurs in children and young adults. Malignant ectomesenchymomas may form in the head and neck, abdomen, perineum, scrotum, or limbs. Also called ectomesenchymoma.

A soft tissue sarcoma that usually occurs in the limbs, most commonly the legs, and may also occur in the abdomen. Also called malignant fibrous cytoma.

A record of information about a person’s health. A personal medical history may include information about allergies, illnesses, surgeries, immunizations, and results of physical exams and tests. It may also include information about medicines taken and health habits, such as diet and exercise. A family medical history includes health information about a person’s close family members (parents, grandparents, children, brothers, and sisters). This includes their current and past illnesses. A family medical history may show a pattern of certain diseases in a family.

A form of cancer that begins in melanocytes (cells that make the pigment melanin). It may begin in a mole (skin melanoma), but can also begin in other pigmented tissues, such as in the eye or in the intestines.

Refers to cells that develop into connective tissue, blood vessels, and lymphatic tissue.

An instrument that is used to look at cells and other small objects that cannot be seen with the eye alone.

A procedure in which radio waves and a powerful magnet linked to a computer are used to create detailed pictures of areas inside the body. These pictures can show the difference between normal and diseased tissue. MRI makes better images of organs and soft tissue than other scanning techniques, such as computed tomography (CT) or x-ray. MRI is especially useful for imaging the brain, the spine, the soft tissue of joints, and the inside of bones. Also called magnetic resonance imaging, NMRI, and nuclear magnetic resonance imaging.

A bundle of fibers that receives and sends messages between the body and the brain. The messages are sent by chemical and electrical changes in the cells that make up the nerves.

A rare genetic condition that causes brown spots and tumors on the skin, freckling in skin areas not exposed to the sun, tumors on the nerves, and developmental changes in the nervous system, muscles, bone, and skin. Also called NF1.

A part of the body that performs a specific function. For example, the heart is an organ.

A cancer of the bone that usually affects the large bones of the arm or leg. It occurs most commonly in young people and affects more males than females. Also called osteogenic sarcoma.

A specific result or effect that can be measured. Examples of outcomes include decreased pain, reduced tumor size, and improvement of disease.

A doctor who identifies diseases by studying cells and tissues under a microscope.

PDQ is an online database developed and maintained by the National Cancer Institute. Designed to make the most current, credible, and accurate cancer information available to health professionals and the public, PDQ contains peer-reviewed summaries on cancer treatment, screening, prevention, genetics, complementary and alternative medicine, and supportive care; a registry of cancer clinical trials from around the world; and directories of physicians, professionals who provide genetics services, and organizations that provide cancer care. Most of this information, and more specific information about PDQ, can be found on the NCI's Web site at http://www.cancer.gov/cancertopics/pdq. Also called Physician Data Query.

An exam of the body to check for general signs of disease.

Occurring in various distinct forms. In terms of cells, having variation in the size and shape of cells or their nuclei.

A rare tumor found mainly in children and young adults. It usually forms in the skin on the arms and legs. It is slow-growing and usually does not spread to other parts of the body. It is a type of soft tissue tumor.

The original tumor.

The likely outcome or course of a disease; the chance of recovery or recurrence.

A molecule made up of amino acids that are needed for the body to function properly. Proteins are the basis of body structures such as skin and hair and of substances such as enzymes, cytokines, and antibodies.

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). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Also called irradiation and radiotherapy.

To become well and healthy again.

To come back or to return.

Cancer that has recurred (come back), usually after a period of time during which the cancer could not be detected. The cancer may come back to the same place as the original (primary) tumor or to another place in the body. Also called recurrence.

In medicine, an improvement related to treatment.

Cancer that forms in the tissues of the retina (the light-sensitive layers of nerve tissue at the back of the eye). Retinoblastoma usually occurs in children younger than 5 years. It may be hereditary or nonhereditary (sporadic).

Cancer that forms in the soft tissues in a type of muscle called striated muscle. Rhabdomyosarcoma can occur anywhere in the body.

Something that increases the chance of developing a disease. Some examples of risk factors for cancer are age, a family history of certain cancers, use of tobacco products, being exposed to radiation or certain chemicals, infection with certain viruses or bacteria, and certain genetic changes.

A cancer of the bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue.

A tumor of the peripheral nervous system that arises in the nerve sheath (protective covering). It is almost always benign, but rare malignant schwannomas have been reported.

Refers to muscle, fat, fibrous tissue, blood vessels, or other supporting tissue of the body.

A cancer that begins in the muscle, fat, fibrous tissue, blood vessels, or other supporting tissue of the body.

A type of connective tissue cancer in which the cells are spindle-shaped when examined under a microscope.

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.

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

An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.

A layer of connective tissue that lines the cavities of joints, tendon sheaths, and bursae (fluid-filled sacs between tendons and bones). The synovial membrane makes synovial fluid, which has a lubricating function.

A malignant tumor that develops in the synovial membrane of the joints.

Tough, fibrous, cord-like tissue that connects muscle to bone or another structure, such as an eyeball. Tendons help the bone or structure to move.

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

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.

A biopsy procedure that uses an ultrasound imaging device to find an abnormal area of tissue and guide its removal for examination under a microscope.

A term used to describe cells or tissues that do not have specialized ("mature") structures or functions. Undifferentiated cancer cells often grow and spread quickly.

A type of radiation used in the diagnosis and treatment of cancer and other diseases. 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.

Table of Links