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Colorectal Cancer Health Center

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Colorectal Cancer Glossary of Terms


Barium: a substance that, when swallowed or given rectally as an enema, makes the digestive tract visible on X-rays.

Barium enema: a process used to study the colon in which barium is given as an enema (through the rectum). Usually gas is then blown in to make the barium spread over the lining of the colon, producing an outline of the colon on X-ray to reveal any irregularities in the lining, such as a polyp, or growth.

Benign tumor: a non-cancerous growth that usually does not spread to nearby tissues or other parts of the body.

Biofeedback: a technique that gives a person some element of voluntary control over particular bodily functions. An electronic device that produces sight or sound signals is often used.

Biological therapy: see Immunotherapy.

Biopsy: the removal and examination of a sample of tissue with a microscope to see whether cancer cells are present.

Brachytherapy: a form of radiation therapy usually used to treat prostate and other cancers. During the procedure, radioactive seeds are implanted into the prostate gland. The seeds remain in place permanently and become inactive after about 10 months. This technique allows for delivery of a high dose of radiation to the prostate with limited damage to surrounding tissues.

Cancer: a general term for more than 100 diseases in which there is an uncontrolled, abnormal growth of cells. Cancer cells can spread to other parts of the body.

Cannulas: tubes that hold the laparoscope and instruments, and allow access to the abdominal cavity for performance of laparoscopic surgery.

Carcinoma: a malignant (cancerous) growth that begins in the lining or covering of an organ and tends to invade surrounding tissue and travel to and grow in other regions of the body.

Carcinoma in situ: cancer that involves only the tissue in which it began; it has not spread to other tissues.

Catheter: a thin, flexible, plastic tube. A urinary catheter is a tube that is inserted into the bladder to drain urine.

CAT scan: a technique in which multiple X-rays of the body are taken from different angles in a very short period of time. A computer that displays a series of "slice" images of the body collects these images.

Chemotherapy: in cancer treatment, chemotherapy refers to the use of drugs whose main effect is either to kill or slow the growth of rapidly multiplying cells. Chemotherapy usually includes a combination of drugs, since this is more effective than a single drug.

Chronic: persisting over a long period of time.

Clear margins: an area of normal tissue that surrounds cancerous tissue, as seen during a microscopic examination. If margins are clear, the surgeon can be virtually sure that he or she has removed all the cancer in that area.

WebMD Medical Reference

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