One in 20. That is an average person’s chance of being diagnosed with colon cancer. Colon cancer is third on the list of most diagnosed cancers and second in cancer-causing deaths. Fortunately, multiple studies have confirmed that colon cancer screening tests improve colon cancer survival rates.
When should you be screened?
Physicians recommend that patients with an average risk of colon cancer undergo screening beginning at age 50. Patients with a family history of colon cancer or a genetic link to colon cancer should to talk to their physicians about being screened earlier.
What screening method should you use?
There are currently multiple colon cancer screening methods available, but there are no head-to-head comparisons showing that one screening test is more effective than another. Each screening test has varying levels of evidence supporting their effectiveness, and each test has its own strengths and weaknesses. Keep in mind that anyone experiencing symptoms like, but not limited to, abdominal pain, blood in the stool, a change in bowel habits or weight loss should see their physician to be evaluated and have the appropriate tests performed. The screening tests described in this article are designed to be performed in patients who are not experiencing GI symptoms.
Although there are many screening options available, the colonoscopy is the most comprehensive test.
Arun Mannem, MD, a gastroenterologist with Charlottesville Gastroenterology Associates, explains, “the colonoscopy not only provides direct visualization of the whole colon but has the added benefit of enabling the removal of precancerous polyps.” If any other screening tests are positive, patients will most likely have to undergo a subsequent colonoscopy to further evaluate or confirm the diagnosis.
While the colonoscopy is an effective and safe test, there may also be reasons why another screening test is performed. A colonoscopy requires a person to undergo a thorough bowel preparation and generally requires some form of sedation. Some patients may have difficulty completing a bowel preparation and may have had difficulties with anesthesia in the past. In addition, the availability and the cost of the procedure may be prohibitive.
“Only about 40% of Virginians get colon cancer screening. A screening test is only useful if a patient is willing to undergo the test; therefore, physicians will accept any approved screening tests.” — Arun Mannem, MD
The US Multi-Society Task Force for Colorectal Cancer recommends that a patient’s first screening test be a colonoscopy or a Fecal Immunochemical Test (FIT), both of which are designated as Tier 1 Screening Tests. There are several other screening methods designated as Tier 2 Screening Tests. These tests are either stool-based, like the FIT test, or direct visualization tests, like the colonoscopy.
Direct Visualization Tests
Colonoscopy [ Tier 1 Screening Test ]
What is it? For a colonoscopy, a doctor uses a colonoscope to screen the entire colon for polyps or cancers. The doctor can pass instruments through the scope to biopsy and/or remove abnormalities. Although the procedure typically takes about 20 minutes, it can take longer if a polyp needs to be removed.
How often should it be performed? It should be done every ten years if the results are normal. People who have had polyps, inflammatory bowel disease or have a family history of colon cancer/colon polyps may need to be tested more frequently.
Pros: The colonoscopy provides a view of the entire colon, enabling the gastroenterologist to view polyps, inflammation and abnormal tissue. It also enables physicians to biopsy and remove polyps.
Cons: The colonoscopy needs to be done by a specialist and can be expensive. It requires full bowel prep, sedation and recovery time. It carries a small risk of bleeding, infection and tears. The procedure can miss small polyps.
Statistic: It is estimated that 60-90 percent of colon cancer deaths could be prevented if everyone over 50 had a colonoscopy. A colonoscopy enables experts to detect 95 percent of cancers and large polyps.