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Colon Cancer Glossary

Adenocarcinomas
A type of colon cancer that starts in the glandular tissue and accounts for 90-95 percent of all colorectal cancers.
Adenomatous polyps (adenomas)
A growth from a mucous membrane frequently found in organs that have the potential to change into cancer.
Adjuvant treatment
Supplementary cancer treatment given after the primary treatment to lower the risk that the cancer will come back; may include chemotherapy, radiation therapy, hormone therapy, targeted therapy or biologic therapy.
Angiography
A test in which a contrast dye is injected directly into a blood vessel that goes to the area that is being studied; a series of x-rays are then taken to show surgeons the location of blood vessels around a tumor.
Ascending colon
The first of the four sections of the colon. The ascending colon begins at the end of the small intestine and extends upward on the right side of the abdomen to connect with the transverse colon.
Benign
Any tumor, growth or cell abnormality that is not cancerous.
Biopsy
The removal of a small portion of tissue to see whether it is cancerous.
Cancer
A group of diseases causing cells in the body to change and grow without control. Most types of cancer cells form a lump or mass called a tumor and the tumor may invade and destroy healthy tissue.
Cancer stage
The assessment of how far a person's cancer has progressed, which influences treatment decisions and prognosis.
Carcinoid
Tumors that develop from neuroendocrine cells (cells that receive input from nerve cells), usually in the digestive tract, lung, or ovary.
Cell
The smallest living unit; all living tissue is composed of cells.
Chemotherapy
A treatment to destroy cancer cells, or keep them from dividing and spreading. Often called chemo.
Colectomy
A surgery that removes all (total colectomy) or part (partial colectomy or hemicolectomy) of the colon.
Colon wall
Several layers of muscle and mucous membrane make up the colon. Starting with the inside layer and moving outward, they are called the mucosa, muscularis mucosa, submucosa, muscularis propria, subserosa, and serosa. Very early cancers that start inside the colon and grow outward may grow through all these layers and invade other organs.
Colonoscopy preparation
The use of a clear liquid diet along with laxatives and enemas to clean out the entire colon before the colonoscopy or virtual colonoscopy is done. This preparation is usually started one to two days before the colonoscopy. Often called prep.
Colonoscopy
A procedure that allows a doctor to see inside the large intestine to find polyps or tumors. The doctor uses a thin (about the thickness of a finger), flexible, hollow, lighted tube that has a tiny video camera. This tube is called a colonoscope. The colonoscope is gently eased inside the colon and sends pictures to a TV screen. Small amounts of air are puffed into the colon to keep it open and allow the doctor to visualize the colon.
CT scan
A computerized tomography (CT) scan that provides images of the body using multiple X-ray images.
Descending colon
The third section of the colon, which starts at the end of the transverse section, and continues downward on the left side of the abdomen (belly) before connecting with the sigmoid colon.
Double contrast barium enema (DCBE)
A test used to help diagnose colorectal cancer. Barium sulfate, a chalky substance, is inserted through the rectum to partly fill and open up the colon. When the colon is about half-full of barium, air is inserted to cause the colon to expand. This allows X-ray films to show abnormal changes in the colon.
Dysplasia
Abnormal changes of groups of cells that may lead to cancer.
External beam radiation therapy (EBRT)
Radiation that is focused from a source outside the body on the area affected by the cancer.
Fecal immunochemical test
A sophisticated laboratory test to look for "hidden" blood in the stool, which could be a sign of cancer.
Fecal occult blood test
A test for "hidden" blood in the stool. The presence of such blood could be a sign of cancer or blood from other sources. The stool is placed on a chemically treated card, pad, or cloth wipe, and then a special chemical solution is put on top of the sample. If the card, pad, or cloth turns blue, there is blood in the stool sample.
Flexible sigmoidoscopy
A procedure in which the doctor looks inside the rectum and the lower portion of the colon (sigmoid colon) through a flexible, lighted tube called a sigmoidoscope.
Gastroenterologist
A doctor who specializes in diagnosing and treating disorders of the digestive system, which includes the esophagus, stomach, pancreas, intestines, and liver.
Gastrointestinal stromal tumors (GISTs)
Tumors that grow from special cells on the intestinal wall. These tumors may or may not be cancer. GIST cancers are very different from other more common types of GI tract cancers in treatment and outlook.
Hyperplastic polyps and inflammatory polyps
Polyps that may become pre-cancerous or might be a sign of having a greater risk of developing adenomas and cancer, particularly when these polyps grow in the ascending colon.
Intestine
The long, tube-shaped organ in the abdomen, which completes the process of digestion. Often called bowel.
Invasive Cancer
Cancer that starts in one area of the body and then spreads to the deeper tissues in that same area.
Large intestine
An organ in the digestive system that processes waste. Often called large bowel.
Localized
Cancer affecting only the cells of a certain area of the body.
Lymphomas
Cancers of immune system cells that typically start in lymph nodes, but may also start in the colon, rectum, or other organs.
Malignant
A mass of cancer cells that may invade nearby tissues or spread (metastasize) to distant areas of the body.
Metastasis
The spread of cancer from one area of the body to another.
Magnetic resonance imaging (MRI)
A method of taking pictures of the inside of the body. MRI uses a powerful magnet to send radio waves through the body and the images appear on a computer screen as well as on film.
Pathology report
Describes the characteristics of the biopsied tissue, including the tumor tissue.
Polyp
A growth from a mucous membrane commonly found in organs such as the rectum, the colon, the uterus, and the nose. Polyps may be non-cancerous (benign) or cancerous (malignant).
Positron emission tomography (PET)
A scan that creates a picture of the body after the injection of a very low dose of a radioactive form of a substance such as glucose (sugar). PET scans are especially useful in taking images of the brain, but they are becoming more widely used to find out if cancers of the breast, colon, rectum, ovary, or lung have spread. PET scans may also be used to see how well a tumor is responding to treatment.
Predictive tests
A diagnostic test that predicts the likelihood that a patient will benefit from specific treatments, such as chemotherapy or hormonal treatment.
Prognostic tests
A diagnostic test that measures the likelihood of a cancer to return, grow, or spread outside the primary site.
Radiation therapy
Therapy that uses high-energy rays (beams of light) or radioactive materials to damage cancer cells, making it more difficult for them to grow in number. Often called radiotherapy.
Recurrence
The development of cancerous cells in the same area of the body after cancer treatment.
Small intestine
The longest section of the gastrointestinal tract. It breaks down food and absorbs most of the nutrients. The small intestine leads into the colon.
Sigmoid colon
The fourth section of the colon. It is known as the sigmoid colon because of its S-shape. The sigmoid colon attaches to the rectum, which in turn connects to the anus, the opening where waste matter passes out of the body.
Sigmoidoscopy
A procedure in which a doctor can look into the rectum and the descending portion of the colon for polyps or other abnormalities.
Stage 0
The earliest stage of colon cancer. The cancer is confined to polyps in the innermost lining of the colon. This is called carcinoma in situ.
Stage I
The polyps have progressed into a tumor and have extended past the innermost layer of the colon to the middle layers of the colon.
Stage II
Cancer has moved beyond the middle layers of the colon to the area surrounding the colon, but not the lymph nodes.
Stage III
Cancer has spread to the lymph nodes surrounding the colon.
Stage IV
The most advanced colon cancer stage. Cancer may have spread to nearby lymph nodes and other vital organs such as the lungs or liver.
Stool
The waste matter discharged in a bowel movement. Often called feces.
TNM system
A common staging system for colorectal cancer, established by the American Joint Committee on Cancer (AJCC.)
T - Tumor
How far the primary tumor has grown into the wall of the intestine and whether it has grown into nearby areas.
N - Nodes
The spread to nearby lymph nodes. Lymph nodes are small collections of immune system cells that are important in fighting infections.
M - Metastasized
When the cancer has spread to other organs of the body.
Total colon exam (TCE)
An exam that looks at the entire colon, also called the large intestine, such as a colonoscopy or double contrast barium enema.
Transverse colon
The second section of the colon or large intestine.
Tumor
An abnormal mass of tissue that can be benign or malignant.
Ultrasound
An imaging test in which high-frequency sound waves are used to outline a part of the body.
Virtual colonoscopy
An examination of the colon for polyps or masses using special computerized tomography (CT) scans. The images are combined by a computer to make a 3-dimensional (3-D) model of the colon.

Sources: Fight Colorectal Cancer and The National Cancer Institute