The task force has found several types of screening tests effective, but the ones most commonly used for those at moderate risk are colonoscopy at a recommended 10-year interval, or FIT annually.
A more recent entry, a home test sold under the brand name Cologuard that detects blood and cancer biomarkers in stool, can be used every three years. However, one study found it to be less effective than most other methods and far more expensive than FIT.
How can FIT compete against colonoscopy when screening is recommended?
Patients at higher risk – including those with colon cancer or parents or siblings with colon cancer, patients with inflammatory bowel disease such as Crohn's disease, and those with abnormal previous tests, including multiple or large polyps – should get a colonoscopy. often on an accelerated schedule. The method includes inserting a viewing instrument through the anus to directly view the colon of an anesthetized patient.
A colonoscopy has one key benefit: if the gastroenterologist detects polyps that can become cancerous over time (although most don't), they can be removed immediately. "You prevent cancer by cutting out the things that could lead to cancer," said Dr. Goodwin. After a negative colonoscopy, patients do not need another for a decade.
However, the complications of the procedure increase with age, although they remain minor. The most serious, a perforated colon, requires hospitalization. Cleansing the bowel the day before the procedure in preparation is bothersome and uncomfortable, and Dr. Goodwin notes that elderly patients sometimes have cycles of diarrhea and constipation for weeks.
Rural residents may have difficulty traveling to an establishment. The use of anesthesia means that every patient needs someone to drive them home or accompany them. The prospect of spending two to four hours in a facility, even if one has strict security measures in place, will cause some older adults to postpone testing over Covid-19 fears.
FIT, which is much more widely used in other countries, avoids many of these difficulties. This is a significant improvement over previous home stool exams. It requires a one day sample instead of three and is not subject to any food or drug restrictions. A positive result still requires a colonoscopy, but the vast majority of patients avoid this result.