Glossary of Terms

Abdominoperineal (AP) resection
Surgery that removes cancer located in the lower part of the rectum, close to its outer connection to the anus.

Destroying a tumor by heating it with microwaves or freezing. This does not involve surgery.

Cancer of the glandular cells, for example, those that line the inside of the colon or rectum.

Adenomatous polyp or adenoma
A benign growth of glandular cells, for example, those that line the inside of the colon or rectum. There are 3 types of colorectal adenomas: tublar, villous and tuberovillous.

Adjuvant therapy
Treatment used in addition to the main treatment. It usually refers to chemotherapy, radiation therapy, immunotherapy or hormonal therapy added after surgery to increase the chances of curing the disease or keeping it in check. Adjuvant therapy is given to treat tumor cells in small numbers that may remain after surgery but cannot be detected.

Alternative therapy
Use of an unproven therapy instead of standard (proven) therapy. Some alternative therapies have dangerous or even life-threatening side effects. With others, the main danger is that the patient may lose the opportunity to benefit from standard therapy. See also complementary therapy.

Anastomosis or anastomotic line
The site where 2 structures are surgically joined together. For example, after removal of a segment of colon containing a cancer, the ends of the colon are reconnected.

The outlet of the digestive tract through which stool passes of out of the body.

Ascending colon
The first of 4 sections of the colon. It extends upward on the right side of the abdomen and leads to the transverse colon.

Not cancer; not malignant.

The removal of a sample of tissues to see whether cancer cells are present. There are several kinds of biopsies. In an endoscopic biopsy, a small sample of tissue is removed using instruments operated through a colonoscope. Click here to view an Olympus colonoscope.

The intestine.

Carcinoembryonic antigen (CAE)
A substance normally found in fetal tissue. If found in an adult, it may suggest that a cancer, especially one starting in the digestive system, may be present. Tests for this substance may help in finding out if a colorectal cancer has recurred after treatment.

Carcinoid Tumors
Tumors which develop from specialized hormone-producing cells of the intestine.

Surgical removal of all (total) or part (partial colectomy or hemicolectomy, for example) of the colon.

Part of the large intestine. The colon is a muscular tube about 5 feet long. It is further divided into 4 sections: the ascending, transverse, descending and sigmoid colon. It continues the process of absorbing water and mineral nutrients from food.

A slender, flexible, hollow lighted tube about the thickness of a finger. It is inserted through the rectum up into the colon. A colonoscope is much longer than a sigmoidoscope and usually allows the doctor to see the entire lining of the colon. The colonoscope is connected to a video camera and video display monitor so that the doctor can look closely at the inside of the colon. If abnormalities are found, the doctor can take a biopsy (tissue sample) or remove polyps, using instruments operated through the colonoscope.

Colorectal Cancer
Colorectal cancer is a term used to refer to cancer that develops in the colon or the rectum. The Colon and rectum are parts of the digestive system, which is also called the gastrointestinal tract, or GI system.

An opening from the colon onto the skin of the abdomen (stomach) for getting rid of body waste (stool). A colostomy is sometimes needed after surgery for cancer of the rectum. People with colon cancer sometimes have a temporary colostomy, but they rarely need a permanent one.

Complementary therapy
Therapies used in addition to standard therapy. Some complementary therapies may help relieve certain symptoms of cancer, relieve side effects of standard cancer therapy, or improve a patientís sense of well-being.

Computed tomography (CT or CAT scan)
A test that uses a rotating x-ray beam to create a series of pictures of the body from many angles. A spiral CT uses a special scanner that can provide greater detail and is sometimes useful in finding metastases from colorectal cancer.

Use of extreme cold to freeze and destroy cancer cells.

Descending colon
The third section of the colon. It comes after the transverse colon, continues downward on the left side of the abdomen and leads to the sigmoid colon.

Digestive system
Also called the gastrointestinal tract, or GI tract. It processes food to obtain energy and rids the body of solid waste matter.

Double contrast barium enema
A method used to help diagnose colorectal cancer. Barium sulfate, a chalky substance, is used to partially 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 abnormalities of the colon.

Endocavitary radiation therapy
A type of radiation therapy used for treating rectal cancer. The radiation beam is aimed through the anus, into the rectum.

Enterostomal therapist
A health professional, often a nurse, who teaches people how to care for ostomies (surgically created openings such as a colostomy) and other wounds.

External beam radiation
The most common way to deliver radiation to a cancer. Radiation is focused from a source outside the body on the area affected by the cancer. It is much like getting a diagnostic x-ray, but for a longer time.

Familial adenomatous polyposis (FAP)
A hereditary condition that is a risk factor for colorectal cancer. People with this syndrome typically develop hundreds of polyps in the colon and rectum. Usually 1 or more of these polyps becomes cancerous if preventive surgery is not done.

Fecal occult blood test (FOBT)
A test for occult (hidden) blood in the stool. The presence of such blood could be a sign of cancer.

Solid waste matter; bowel movement or stool.

Gastrointestinal stromal tumors
Tumors which develop from specialized cells in the wall of the colon called the 'interstitial cells of Cajal.' Some are benign; others are malignant.

Hereditary nonpolpsis colorectal cancer (HNPCC)
People with this condition are at increased risk of developing colorectal cancer without first having many polyps.

Treatments to help the immune system recognize and destroy cancer cells more effectively. These may include cancer vaccines and monoclonal antibody therapy.

A long slender tube inserted into the abdomen through a very small incision. Surgeons with experience in laparoscopy can do some types of surgery for colorectal cancer using special surgical instruments operated through the laparoscope.

Cancers of the immune system cells that typically develop in lymph nodes but also may start in the colon and rectum or other organs.

Low anterior (LA) resection
Surgery that removes a cancer and the normal tissue around it near the upper part of the rectum, close to where it connects with the sigmoid colon.

Lymph nodes
Small bean-shaped collections of immune system cells that help fight infections and also have a role in fighting cancer. Also called lymph glands. Cancers of the colon and rectum may spread to nearby lymph nodes.

Edge of the tissue removed during surgery. A negative surgical margin is usually a sign that no cancer was left behind near the area it was removed from. A negative surgical margin does not guarantee a cure because cancer cells my have spread to other areas of the body before surgery. A positive surgical margin indicates that cancer cells are found at the outer edge of the tissue are removed and is usually a sign that some cancer remains in the body.

The spread of cancer cells to distant areas of the body by way of lymph system or bloodstream.

Neoadjuvant therapy
Treatment given before the primary treatment of radiation or surgery. However, radiation can also be a part of neoadjuvant treatment.

A doctor who specializes in diagnosis and classification of diseases by laboratory tests such as examination of tissue and cells under a microscope. The pathologist determines whether a tumor is benign or cancerous, and, if cancerous, the exact cell type and grade.

A benign growth commonly found in the rectum or the colon. Adenomatous polyps sometimes turn into cancer. Many other types of polyps (inflammatory polyps, hyperplastic polyps) do not.

Radiation colitis
Irritation of the colon caused by radiation therapy. Problems can include pain, cramping and diarrhea.

Radiation proctitis
Irritation of the rectum caused by radiation. Problems can include pain, bowel frequency, bowel urgency, bleeding, chronic burning or rectal leakage.

The lower part of the large intestine, just above the anus.

Cancer that has come back after treatment. Local recurrence means that the cancer has come back at the same place as the original cancer. Regional recurrence means that the cancer has come back after treatment in the lymph nodes or tissues near the primary site. Distant recurrence is when cancer metastazixes after treatment to organs or tissues (such as lungs, liver, bone marrow, or brain) farther from the original site than the regional lymph nodes.

Risk factor
Anything that increases a person's chance of getting a disease such as cancer. Different cancers have different risk factors. For example, unprotected exposure to strong sunlight is a risk factor for skin cancer. Some risk factors, such as smoking or an unhealthy diet, can be controlled. Others, like a person's age or family history, cannot be changed.

The search for disease, such as cancer, in people without symptoms. For example, screening tests for early detection of colorectal cancer include fecal occult blood test, flexible sigmoidoscopy, colonoscopy and double contrast barium enema.

Segmental resection
In this surgery, the cancer and a length of normal tissue on either side of the cancer as well as the nearby lymph nodes are removed. The remaining sections of the colon are then attached back together.

Sigmoid colon
The fourth section of the colon is known as the sigmoid colon because of its S-shape. The sigmoid colon joins the rectum, which in turn joins the anus, or the opening where waste matter passes out of the body.

A slender, flexible, hollow, lighted tube about the thickness of a finger. It is inserted through the rectum up into the colon. This allows the doctor to look at the inside of the rectum and part of the colon for cancer or for polyps.

Small intestine
The small intestine is the longest section of the GI tract. It breaks down food and absorbs most of the nutrients. The small intestine joins the colon and is also known as the small bowel.

Extent of disease. Clinical stage refers to the extent of disease determined by the physical examination and imaging tests. The pathologic stage is determined by examination of the e tissue after surgery.

Solid waste matter; feces.

Transverse colon
The second section of the colon, following the ascending colon and leading to the descending colon. It is called the transverse colon because it goes across the body to the left side.

An abnormal lump or mass of tissue. Tumors can be benign (not cancerous) or malignant (cancerous).

Ulcerative colitis
A type of inflammatory bowel disease. In this condition, the colon is inflamed for a long time. This increases a person's risk of developing colon cancer, so starting colorectal cancer screening earlier and doing these tests more often is recommended.

High frequency sound waves used to produce images of body tissue. Two special types of ultrasound examinations are used to evaluate people with colon and rectal cancer. The endorectal ultrasound uses a special transducer that can be inserted directly into the rectum. This test is used to see how far a rectal cancer may have penetrated and whether it has spread to nearby organs or tissues. The intraoperative ultrasound is done after the surgeon has opened the abdominal cavity. It is used for detecting colorectal cancer that may have spread to the liver.

Upper endoscopy
Inspection of the upper part of the digestive system using a flexible, lighted tube know as an endoscope.

The glossary of terms and definitions where provided by the American Cancer Society and have been published in their publication titled The Colon and Rectal Cancer Treatment Guidelines for Patients. For more information about this publication or the American Cancer Society, visit