The purpose of colon cancer screening is to detect the presence of cancer before symptoms appear. Colon cancer screenings for individuals between 50 and 75 years of age are highly recommended because colon cancer can actually be prevented.
With all the different colonoscopy screenings available to you, how do you choose which screening test is the best? Here are a few of the most common colon cancer screening methods, from most invasive to least invasive:
Colonoscopy
A colonoscopy allows your doctor to view the entire length of your colon to evaluate the health of your digestive tract. Using a long, flexible tube called a colonoscope, your doctor will insert the tube into your rectum. A camera attached to the tube will help your doctor see any abnormalities. If any polyps are discovered during the procedure, your doctor can remove the polyps during the procedure for biopsy and diagnosis. If you receive a clean bill of health after your colonoscopy, you likely will not have to schedule another procedure for ten years.
Flexible sigmoidoscopy
A flexible sigmoidoscopy is much like a colonoscopy, but it only allows your gastroenterologist to view a portion of your colon and rectum. It is a simpler bowel prep than a colonoscopy, and you likely will not need to be sedated. Polyps can be detected and removed during a colonoscopy, but polyps can only be detected in part of the colon. Often you have to repeat the test every five years instead of every ten years.
Virtual Colonoscopy and Double Contrast Barium Enema
Virtual colonoscopy and double contrast barium enema are two colon cancer screening methods that are less invasive and more affordable than a colonoscopy. Using computerized tomography (CT) and x-rays, these two exams are useful for detecting abnormalities in the GI tract. Although they are not as comprehensive as a colonoscopy, they can help detect colon issues such as diverticulitis, inflammatory bowel disease and structural changes in the intestines.
Stool tests
Two tests which are less invasive but mainly detect cancer are guaiac-based fecal occult blood test (FOBT) and fecal immunochemical test (FIT). These tests can indicate colorectal cancer, but not diagnose it. Both tests are qualitative tests, which check for the presence or absence of blood in the stool. If blood is detected, additional testing would be required to determine the source of the blood. These tests are often recommended once per year.
Although each screening method has its merits, the colonoscopy continues to be the gold standard for colon screening. In a single procedure, a colonoscopy can examine the colon from the cecum to the rectum, remove precancerous polyps and diagnose gastrointestinal conditions. No other screening has the same preventative, therapeutic and diagnostic abilities. Because of this, the colonoscopy still reigns supreme as the most thorough, effective and comprehensive exam (Source: American Cancer Society).