Every day, normal cells from the colon as well as abnormal ones from precancerous polyps are shed into your stool. The Cologuard test looks for DNA and blood that is released into the stool as these cells are shed. People can collect their own stool sample at home using a kit and then send it to the lab for advanced testing.
The test is not a replacement for a colonoscopy, but rather a screening tool for people who have an average risk of colorectal cancer. It can detect certain proteins that are shed from the colon and precancerous polyps. It is a much less invasive option than a colonoscopy, avoiding issues such as reactions to sedatives and puncturing of the bowels.
However, it does not find all polyps, including dangerous large ones. The test misses 42% of these, compared to 92% for a colonoscopy. And it has a false positive rate of 13%, which increases as people age.
A positive result can cause anxiety, but it is important to remember that only a small percentage of positive results are cancer. It is also important to discuss any concerns you have with your doctor.
Fortunately, the test is covered by most private insurance plans and Medicare. The Affordable Care Act ensures that individuals do not have to incur any out-of-pocket costs, including deductibles and co-pays, for preventive tests such as Cologuard. This can help ease anxiety about potential follow-up procedures.