Glossary

Adenomaa growth in the epithelial layer of the colon. Growths can be flat, pedunculated, or sessile. They result from multiple genetic mutations arising from environmental or inherited causes. Colorectal adenomas can progress to become cancerous.

Adherencehow closely patients comply with recommended medical treatment, therapy, or testing.

Cecum (cecal)a pouch-like section of the ascending colon, located where the small intestine joins the large intestine (colon). For colonoscopies, this is the farthest point from the rectum observed using the procedure.

Co-insurancethe percentage of medical care costs covered by an insured individual beyond the deductible. In many cases, co-insurance is paid by the insured individual until a predefined limit is reached, after which all costs are covered by the health care plan. Co-insurance also is used to refer to supplemental insurance used to pay the fees not covered by the primary health care plan. Co-insurance is often synonymous with “copayment” which is often shortened to “copay.”

Colonbegins at the end of the small intestine. The components of the colon, in order of the anatomy, are: the cecum, ascending colon, hepatic flexure (the turn near the liver), transverse colon, splenic flexure (the turn



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Glossary Adenoma—a growth in the epithelial layer of the colon. Growths can be flat, pedunculated, or sessile. They result from multiple genetic mutations arising from environmental or inherited causes. Colorectal adenomas can progress to become cancerous. Adherence—how closely patients comply with recommended medical treatment, therapy, or testing. Cecum (cecal)—a pouch-like section of the ascending colon, located where the small intestine joins the large intestine (colon). For colonoscopies, this is the farthest point from the rectum observed using the procedure. Co-insurance—the percentage of medical care costs covered by an insured individual beyond the deductible. In many cases, co-insurance is paid by the insured individual until a predefined limit is reached, after which all costs are covered by the health care plan. Co-insurance also is used to refer to supplemental insurance used to pay the fees not covered by the primary health care plan. Co-insurance is often synonymous with “copay- ment” which is often shortened to “copay.” Colon—begins at the end of the small intestine. The components of the colon, in order of the anatomy, are: the cecum, ascending colon, hepatic flexure (the turn near the liver), transverse colon, splenic flexure (the turn 

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 IMPLEMENTING COLORECTAL CANCER SCREENING near the spleen), descending colon, and sigmoid colon. The colon ends at the rectum. Colonoscopy—an endoscopic procedure used to detect colorectal pol- yps and cancers. Colonoscopy uses an imaging scope inserted through the rectum and colon, up to the cecum. Adenomas larger than 1 cm are often removed during the procedure. This is also known as optical colonoscopy. Copayment—the percentage of medical care costs covered by an insured individual beyond the deductible. Copayment is often short- ened to “copay,” and is often synonymous with “co-insurance.” See also Co-insurance. Crohn’s Disease—a type of inflammatory bowel disease which is char- acterized by chronic inflammation of the digestive tract. In Crohn’s dis- ease, this inflammation is usually located in one or both of the ileum or colon, but it can occur anywhere in the digestive system. In addition, the inflammation may occur throughout all layers of the intestine. Symptoms include abdominal pain, bleeding, or diarrhea. CT colonography—computed tomography colonography, also known as “virtual” colonoscopy. In this procedure, a 3-D, “fly-through” repre- sentation of the colon is created using computed tomography; it can be examined by a radiologist in the same way as an optical colonoscopy. Computed tomography is a radiographic technique that uses a computer to assimilate multiple X-ray images into two-dimensional, cross-sectional images or a 3-D image. Use of this technique can reveal many soft-tissue structures not shown by conventional radiography. Double-contrast barium enema—an X-ray procedure used to visualize the interior anatomy of the colon. To provide contrast, a barium enema is first administered, followed by insertion of air into the colon. The pro- cedure is called double-contrast due to the contrast-enhancing properties of both the barium and the air. After both contrast agents are in place, an X-ray machine is used to image the colon. Dysplasia—abnormal cells, possibly precancerous. Endoscopist—person who performs endoscopies. Endoscopy—use of a camera inserted into the body to determine the physical appearance of internal organs or tissues. Colonoscopy and flex-

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 GLOSSARY ible sigmoidoscopy are common types of colorectal endoscopy. The term endoscopy also refers to examination of the upper gastrointestinal tract (i.e., mouth, esophagus, stomach) using the same methods. Fecal DNA test—a test using genetic signature to predict presence of colorectal polyps or cancer. The fecal samples examined contain DNA from exfoliated colorectal cells. Fecal immunochemical test—FIT. This is a home-administered test to detect blood—specifically hemoglobin—in a patient’s stool. Blood in the stool may indicate bleeding colorectal adenomas or carcinomas. The patient prepares the sample and then mails it to the laboratory for development and detection. If a positive result is found, colonoscopy is indicated. First-dollar health coverage—health insurance that begins paying bene- fits with the first use of services, not only after payment of a deductible. Flexible Sigmoidoscopy—an endoscopic screening method for detecting colorectal polyps and cancer. Like colonoscopy, flexible sigmoidoscopy uses an imaging scope inserted through the rectum and colon. Unlike colonoscopy, however, flexible sigmoidoscopy only investigates the rec- tum, sigmoid colon, and descending colon only. FOBT—fecal occult blood test. This is a home-administered test to detect blood in a patient’s stool. Blood in the stool may indicate bleeding colorec- tal adenomas or carcinomas The patient prepares the sample, then mails it to the laboratory for development and detection. If a positive result is found, colonoscopy is indicated. Hyperplastic—pertaining to increased cell proliferation, but where the cells remain essentially normal. Inflammatory Bowel Disease—a series of diseases affecting the colon and other parts of the digestive system. The two main types of inflammatory bowel disease are Crohn’s disease and ulcerative colitis. Intubation—insertion of an endoscope or other instrument into a bodily orifice. In the case of colonoscopy or sigmoidoscopy, this refers to inser- tion of the endoscope into the colon. Medicaid—a state-administered health care program for specified groups of low-income individuals and families. Eligibility criteria vary by state,

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 IMPLEMENTING COLORECTAL CANCER SCREENING and they can include factors such as income, disability status, age, immi- gration status, and more. Medicare—a health care program for individuals aged 65 and older. Includes Part A for coverage of hospitalization-related expenses, Part B for coverage of medical care, and prescription drug coverage. Metastasis—the spread of cancer from its site of origin to other parts of the body. Presence of metastases often indicates more advanced cancer. Neoplastic—pertaining to abnormal new growth of cells. A neoplasia may be considered precancerous. Occult—hidden, but possible to discover upon inspection. Patient navigation—helping a patient work his or her way through a health care system. Polyp—a colorectal adenoma (see Adenoma). Polypectomy—removal of a polyp, often during colonoscopy, a procedure that can prevent colorectal cancer. PSA test—a blood test that detects prostate-specific antigen (PSA). The PSA test was approved by the Food and Drug Administration in 1985 for prostate cancer recurrence, but it is now widely used as a screening test for prostate cancer. While testing for prostate-specific antigen (PSA) can successfully detect prostate cancer, many believe that the practice has led to treatment of small tumors not likely to progress and that this treatment does not lead to decreased mortality from the disease (Lilja et al., 2008). Screening initiative—a program started by a community, health organi- zation, or another entity to screen certain groups of people for colorectal cancer. Sensitivity—a measurement of how often a test correctly identifies patients with a specific diagnosis, or the fraction of positive results that are correct. It is calculated as the number of true-positive results divided by the sum of true-positive and false-negative results. In this summary, sensitivities of various colorectal cancer screening tests are discussed. Sigmoid (sigmoid colon)—the curved portion of the colon between the rectum and the descending colon.

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 GLOSSARY Specificity—a measurement of how often a test correctly identifies the proportion of persons without a previous diagnosis, or the fraction of negative results that are correct. It is calculated as the number of true- negative results divided by the sum of true negatives and false positives. In this summary, specificities of various colorectal cancer screening tests are discussed. Stage—The TNM classification system is used to stage colorectal cancer (ACS, 2008; NCI, 2008). T refers to the characteristics of the primary tumor, N refers to the involvement of regional lymph nodes, and M refers to the extent of metastasis, if any. The TNM stages are then grouped into familiar numbered stages, 0–4. Stage 0 refers to highly localized cancers that have not grown beyond the inner layers of the colon or rectum. Stage 1 refers to cancers that have penetrated the inner layers of the colon or rectum, but not to the outer layers. Stage 2 refers to cancers that have penetrated all layers of the colon or rectum, may or may not have reached adjacent tissues, but has not reached lymph nodes or distant sites. Stage 3 refers to cancers that have spread to one or a few nearby lymph nodes, and it may or may not have spread to nearby organs. Stage 4 refers to cancers that have spread to distant sites. For more infor- mation, see http://www.cancer.org/docroot/CRI/content/CRI_2_4_3X _How_is_colon_and_rectum_cancer_staged.asp or http://www.cancer .gov/cancertopics/pdq/treatment/colon/HealthProfessional/page4. Ulcerative Colitis—a type of inflammatory bowel disease which is char- acterized by chronic inflammation of the digestive tract. In ulcerative colitis, this inflammation is usually located in the colon or rectum. In addi- tion, the inflammation occurs only in the lining of the intestine. Symptoms include abdominal pain, bleeding, or diarrhea. Uptake—the rate at which individuals begin to comply with recom- mended medical care.