Glossary of Cancer Terms



Small deposits of calcium in the tissue, which can be seen on mammograms.


A mineral found mainly in the hard part of bones.


A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearly tissues and can spread through the bloodstream and lymphatic system to other parts of the body.

Cancer of Unknown Primary Cancer cells are found in the body, but the place where the cells first started growing (the origin or primary site) cannot be determined.
Cancers of the Eye There are two main types of cancer which can affect the eye, intraocular melanoma which affects the uvea and retinoblastoma which affects the retina.


Substances or agents that are known to cause cancer.

Carcinoid A tumor which may secrete large amounts of the hormone serotinin. The tumor usually arises in the gastrointestinal tract anywhere between the stomach and the rectum (the favorite spot is in the appendix) and from there may metastasize (spread) to the liver. In the liver the tumor produces and may release large quantities of serotonin into the systemic bloodstream.


Cancer that begins in the skin or in tissue that line or cover internal organs.

Carcinoma in Situ

Cancer that is confined to the cells where it began and has not spread to surrounding tissues.

Carney Complex A multiple endocrine neoplasm which is associated with heart and skin tumors.


A person who has a recessive mutated gene, together with its normal allele. Carriers do not usually develop disease, but can pass the mutated gene on to their children.

Carrier testing

Testing to identify individuals who carry disease-causing recessive genes that could be inherited by their children. Carrier testing is designed for healthy people who have no symptoms of disease, but are known to be at high risk because of family history.


Firm, rubbery tissue that cushions bones at joints. A more flexible kind of cartilage connects muscles with bones and makes up other parts of the body, such as the larynx and the outside parts of the ears.


A flexible tube that is placed in a body cavity to insert or withdraw fluids.

(Diathermy or electrodiathermy)

The use of heat to destroy tissue.


Community Clinical Oncology Program. This program links community physicians with National Cancer Institute (NCI) clinical research programs, so that more cancer patients can participate in clinical trials in their own communities.


The smallest unit of tissues that make up any living thing. Cells have very specialized structure and function and are able to reproduce when needed.

Central line

Thin, flexible tube placed in a large blood vessel (e.g. subclavian vein). Used to deliver fluids or medication and withdraw blood.

Central nervous system (CNS)

The brain and spinal cord.

Central venous catheter

A special thin, flexible tube placed in a large vein. It remains for as long as it is needed to deliver and withdraw fluids.


The portion of the brain in the back of the head between the cerebrum and the brain stem.

Cerebral hemispheres

The two halves of the cerebrum.

Cerebral spinal fluid (CSF)

The watery fluid flowing around the brain and spinal cord.

Cervical Cancer The development of cancer cells on the cervix. Most cervical cancers are squamous cell cancers. Cervical cancer is thought to be related to human papilloma virus (HPV).

Cervical intraepithelial neoplasia (CIN)

A grading scale used to describe the growth of abnormal cells on the surface of the cervix. Scale from 1(mildly abnormal) to 3 (severely abnormal).


The lower, narrow end of the uterus that forms a canal between the uterus and the vagina.


Attempting to prevent cancer through the use of drugs, chemicals, vitamins or minerals.

Chemoprevention studies

Also called “cancer prevention studies.” Cancer prevention studies test whether the study agent—usually drugs, vitamins, minerals, food supplements, or a combination of them can reduce a person’s chances of getting cancer.


Treatment of cancer by the use of chemicals (drugs) designed to kill cancer cells or stop them from growing.

Cholangiocarcinoma (Cancer of the bile duct) Bile duct cancer is a rare cancer. Since bile ducts are located throughout the liver, bile duct cancer can ocurr in many locations in and around the liver. The bile ducts are tubes that connect the liver and the gallbladder to the small intestine. Bile is manufactured in the liver and helps with the digestion of fats.
Chondrosarcoma Sarcomas are uncommon malignant tumors that begin either in bones or in soft tissues such as muscles, cartilage, fat or connective tissue. They make up about 1% of cancers in adults and 15% in children. Chondrosarcomas tend to affect the older age groups (50 to 60 years). The tissue of origin for chondrosarcomas is the cartilage. There are three tumor categories related to the tumor's grade or activity; low, intermediate and high grade. High grade are the faster growing cancers.


The fundamental strands of genetic material (DNA) that carry all of our genes. There are 23 pairs in each cell. Tumor cells sometimes have more or less than 23 pairs.

Chronic Leukemia A cancer of the white blood cells. Unlike acute leukemia the cells go through all of the stages of formation with only few blasts (immature cells) forming. The cells may look normal but do not function normally. Treatment may be close observation in early stages or control with medication over years.
Chronic Lymphocytic Leukemia (CLL) A chronic leukemia affecting the lymphocytes (a type of white blood cell). Generally it occurs in older persons without symptoms and progresses slowly.
Chronic Myelogenous Leukemia (CML) A chronic leukemia affecting the myeloid cell line. Usually affects people in their 50's or 60's but may occur in infants. If a Philadelphia chromosome abnormality is present on cells 60-70 % will progress to an acute phase.

Chronic pain

Pain that can range from mild to severe, and is present for a long time.

Chronic phase

Refers to the early stages of chronic myelogenous leukemia. The number of immature, abnormal white blood cells in the bone marrow and blood is higher than normal, but lower than in the accelerated or blast phase.



Clear margins

An area of normal tissue that surrounds cancerous tissue, as seen during examination under a microscope.

Clinical trial

A research study that tests how well new medical treatments or other interventions work in people. Each study is designed to test new methods of screening, prevention, diagnosis, or treatment of a disease.


A strain of cells - whether normal or malignant - that come from a single original cell.


The process of making genetically identical copies.

CNS prophylaxis

Chemotherapy or radiation therapy to the central nervous system (CNS). This is a preventative treatment. It is given to kill cancer cells that may be in the brain and spinal cord, even though no cancer has been detected there.

Cobalt 60

A radioactive substance used as a radiation source to treat cancer.


The lower 5-6 feet of the intestine. The colon is also called the large bowel or large intestine.

Colon Cancer Cancer of the large intestine. It is highly treatable and often curable when it is localized and diagnosed in the early stages. When it has spread through the bowel wall to lymph nodes or nearby organs the chances of cure are reduced.

Colon Polyps

Abnormal growth of tissue on the lining of the bowel. Polyps are a risk factor for cancer of the bowel.


An examination in which the doctor looks at the colon through a flexible, lighted instrument called a colonoscope.

Colony-stimulating factors

A substance that stimulates the growth of bone marrow cells.

Colorectal Cancer Cancer of the colon and rectum. A malignant tumor arising from the inner wall of the large intestine.


A procedure in which a lighted magnifying instrument is used to examine the vagina and cervix.

Combination chemotherapy

Use of two or more anticancer drugs.

Combination therapy

The use of two or more modes of treatment—surgery, radiation therapy, chemotherapy, or immunotherapy—in combination, alternately or together, to achieve optimum results against cancer.

Common bile duct

Bile ducts are passageways that carry bile. Two major bile ducts join together to form the common bile duct, which empties into the upper part of the small intestine (the part next to the stomach).

Computed tomography (CT or CAT) scan

An imaging technique that uses a computer to organize the information from multiple x-ray views and construct a cross-sectional image of the part of the body being scanned. This technique is used to identify areas that may be cancer or metastases.

Condylomata Acuminata

Genital warts caused by certain human papillomaviruses.

(Cone biopsy)

Surgery to remove a cone-shaped piece of tissue from the cervix and cervical canal. Conization may be used to diagnose or treat a cervical condition.

Consent form

A document that provides key facts about a clinical trial. This includes information about the study agent, tests that study participants may have, and possible benefits and risks. Although all participants in a clinical trial must sign a consent form, they can leave the study at any time. As a trial proceeds, there may be updates to the information on the original consent form.

Continent reservoir

A pouch formed from a piece of small intestine to hold urine after the bladder has been removed.

Control group

In a clinical trial, the group of people that receives standard treatment for their cancer.

Core needle biopsy

The use of a small cutting needle to remove a core of tissue for microscopic examination.


The body of the uterus.


A benign tumor located near the pituitary gland, represents about 5-13% of pediatric brain tumors.


An incision through the skull.


Treatment performed with an instrument that freezes and destroys abnormal tissue.

(Undescended testicle)

A condition in which one or both testicles fail to move from the abdomen, where they develop before birth, into the scrotum.


Related to the skin.

Cutaneous T-Cell Lymphoma (CTCL) Neoplasms of the T lymphocytes, which effect the skin. Mycosis fungoides, Se'zary syndrome, reticulum cell sarcoma of the skin are all different clinical presentations of CTCL. CTCL is a relatively rare neoplasm. The incidence rises with age and the majority of those affected are between 40 and 60 years old. More common in males than females.

Cyclic breast changes

Normal tissue changes that occur in response to the changing levels of female hormones during the menstrual cycle. Cyclic breast changes can produce swelling, tenderness, and pain.


A sac or capsule filled with fluid.


Surgery to remove the bladder. In a partial cystectomy, only part of the bladder is removed. During radical cystectomy, the entire bladder, the fat and tissue surrounding the bladder and the pelvic lymph nodes are removed. In men the prostate and seminal vesicles are also removed. In women the uterus, tubes, ovaries, anterior vaginal wall and urethra are removed.


A thin, lighted instrument used to examine the interior of the bladder.


A procedure in which the doctor inserts a lighted instrument into the urethra (the tube leading from the bladder to the outside of the body) to look at the bladder.


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