Although it’s one of the most unpopular screening exams around, colonoscopy is one of the most important. Unlike other common cancer screening tests, this one allows physicians to prevent cancer, potentially saving thousands of lives each year.

The U.S. Centers for Disease Control and Prevention notes that colon cancer is the second-leading cause of cancer death in the nation. However, the CDC reports that rates of new cases and deaths of colorectal cancer are decreasing, and more adults are being screened. Between 2003 and 2007, approximately 66,000 colorectal cancer cases were prevented and 32,000 lives were saved, compared to 2002. Half of these prevented cases and deaths were due to screening, the report states.

“Most colon cancers start as small, typically benign polyps on the surface of the colon lining,” explains Dr. Paul Buse, associate director of Mercy Clinic Digestive Disease. “Over time, a polyp can increase in size, and as size increases, so does the probability it will evolve into cancer. During a screening colonoscopy, your gastroenterologist will remove any polyps. Removal of polyps can prevent colon cancer from occurring.”

Current guidelines call for screening colonoscopy to begin at age 50. Patients who have a close relative (parent or sibling) diagnosed with colon cancer should be screened sooner. Subsequent screening depends on whether polyps are found and removed during the initial colonoscopy, but typical screening schedules suggest colonoscopy every three to five years for those who had polyps and every 10 years for those who did not and who do not have a family history of colon cancer.

“The most dreaded part of a colonoscopy is the bowel preparation, and that is easier now because of Gatorade/Miralax bowel preparations,” says Dr. Jeffrey Kreikemeier, a physician with Gateway Gastroenterology and on staff at St. Luke’s Hospital. The bowel must be emptied prior to the test, and this is achieved using laxatives the day prior to the test.

While the pre-test preparation is the worst part of the entire experience, the test itself is usually well tolerated. “The anesthetic agents allow most patients to sleep comfortably and soundly through the exam,” Buse says. “The anesthetic agents that we use are relatively short-acting so that by the time a patient is discharged, the patient is relatively awake and coherent. It is still imperative that you not drive or make important decisions for the rest of the day.”

Patients who cannot have a traditional colonoscopy, in which a scope on a thin, flexible tube is inserted into the colon through the rectum while the patient is under anesthesia, may undergo ‘virtual colonoscopy.’ This exam, which does not require anesthesia, involves a CT scan of the abdomen and pelvis and still requires bowel preparation and the need to pump air into the colon so it can be better visualized.

“Colonoscopy is a simple, safe and effective way to prevent colon cancer and colon cancer-related deaths,” Buse says. “The 20 minutes that you or a friend or loved one spends having a colonoscopy could be life-saving. Please, don’t be embarrassed to death.”

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