Colorectal cancer is the third leading type of cancer in both males and females in the United States; of the cancers that affect both genders, it is the second most fatal, trailing only lung cancer. Most colorectal cancers develop from polyps, which are clumps of cells on the walls of the colon. Most polyps are harmless and asymptomatic, and, when detected early, can be removed safely and easily before they have the opportunity to become cancerous. Virtual and traditional colonoscopy are important tools in the early detection of pre-cancerous polyps.
What is My Risk for Colorectal Cancer?
Since colon polyps and early colon cancer can exist without symptoms, regular screening is important. For men and women who are at average risk for developing colorectal cancers, the American Cancer Society (ACS) recommends testing for both polyps and cancer starting at age 50. Men have a higher overall risk of developing colorectal cancer, and the risk increases for both men and women as they get older. Out of every 100 men who are 60 years old today, on average, 1-2 will develop colorectal cancer by the time they are 70; by the time they are 80, 2-3 will likely have been affected.
Factors that increase a person’s risk for cancers of the colon and rectum include colon polyps, long-standing inflammatory bowel disease, and genetic family history of a colorectal cancer syndrome such as familial adenomatous polyposis (FAP) or hereditary non-polyposis colon cancer (HNPCC). For individuals who have any of these additional risk factors, the ACS recommends screening earlier and/or more frequently.
Screening Options to Find Polyps or Cancer
Colorectal cancer is treatable and has an excellent survival rate when diagnosed early. A variety of screening tests are available for polyps and cancer, including conventional colonoscopy, which the ACS advises normal-risk individuals undergo every ten years, and virtual colonoscopy, which should be repeated every five years. People at increased risk are advised to screen earlier and/or more often, so you should discuss your risk level and screening options with your health care provider to choose the best course for you and consult with your health insurance provider on coverage as some policies do not cover virtual colonoscopies.
A traditional optical colonoscopy is one of the best ways to detect abnormalities, precancerous indications, or early-stage cancer. In this procedure, a doctor inserts a small, flexible camera tube into the colon through the rectum to visually inspect the lining of the colon. Although very effective, colonoscopies can be uncomfortable and difficult to schedule into a busy lifestyle.
CT colonography, also known as virtual colonoscopy, is an alternative. This minimally invasive procedure uses a computed tomography (CT) scan to examine the colon from the outside. Like other CT scans, it uses x-rays to generate detailed cross sectional images of the inside of the body. A radiologist then examines the scans for polyps and other abnormalities. Because it is less invasive than conventional colonoscopy and does not usually require sedation, it has a lower risk of complications and is more convenient.
A more invasive optical colonoscopy is typically unnecessary unless your doctor discovers a polyp or abnormality. According to the American College of Gastroenterology, depending on the age of the patient, the odds of being called back for a colonoscopy and polypectomy after a virtual colonoscopy are approximately 12-25%.
Because colorectal screening is so effective in facilitating early detection of polyps and abnormalities and preventing colorectal cancer, it is often covered by insurance. Check with your insurance company to determine whether and to what extent your insurance provider offers coverage for this procedure.
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