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Colorectal Cancer Glossary of Terms


Mismatch repair: DNA constantly has to produce new strands of itself. When this is done incorrectly, there are special genes involved in correcting the mistake. If this is not done, or not done properly, a tumor can grow in the place of normal cells.

Muscle transposition: a procedure that borrows a working muscle to replace one that isn't working.

Mutation: a change in a gene with the potential of being transmitted to children.

Nausea: a queasy feeling that leads to stomach distress, a distaste for food, and an urge to vomit. Nausea is not a disease, but a symptom of many diseases. It can be brought on by illnesses such as influenza, medications, pain, and inner ear disease.

Nitrates: substances found in some foods, especially meats, prepared by drying, smoking, salting or pickling. Nitrates are thought to cause cancer.

Non-steroidal anti-inflammatory drugs (NSAIDs): drugs that reduce inflammation and pain that do not contain steroids. Examples of these drugs include aspirin, naproxen, and ibuprofen.

Occult blood: blood in the stool that is not visible to the naked eye. This type of bleeding is detected by performing a laboratory test on a stool sample.

Oncologist, medical: a doctor who specializes in the medical treatment of cancer. Medical oncologists have expert knowledge of how cancers behave and grow. This knowledge is used to calculate your risk of recurrence as well as the possible need for, and benefits of, additional or adjuvant therapy (such as chemotherapy, hormonal therapy or bone marrow transplantation). Your medical oncologist generally manages your overall medical care and monitors your general health during your course of treatment. He or she checks your progress frequently, reviews your lab and X-ray results and coordinates your medical care before and after your course of treatment.

Oncologist, radiation: a doctor trained in cancer treatment using radiation therapy.

Oncologist, surgical: a doctor who performs biopsies and other surgical procedures to diagnose and treat cancer.

Ostomy: a general term meaning an opening, especially one made by surgery; see also Colostomy.

Pathology: the study of the characteristics, causes, and effects of a disease.

Pathologist: an expert who specializes in analyzing tissue samples (removed during a biopsy) under a microscope to detect the cellular makeup of the tumor, whether the cancer is in just one place, whether it has the potential to spread, and how quickly it is growing. Pathologists can detect subtle differences in cancer cells that help your surgeon and oncologist confirm the diagnosis.

PCA: patient controlled analgesia, or PCA, is a method of administering pain medication that is activated by the patient.

Peristalsis: the means by which food or waste is propelled through the gastrointestinal tract in a series of muscular contractions.

Platelets: substance in blood that helps prevent bleeding by causing blood clots to form at the site of an injury.

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