In the United States, the average lifetime risk of colon cancer is about one in 20, according to the American Cancer Society. In each of the past several years, more than 50,000 Americans have died of the disease—but the death rate has been declining for a couple decades, partly because of screening.
Although a colonoscopy is the most effective method of detecting colorectal cancer at an early stage, there are other tests your doctor may prescribe for you that are less invasive.
The Fecal Immunochemical Test (FIT) is a newer version of the fecal occult blood test (FOBT) that detects minute traces of blood in the stool. This colon cancer test:
Detecting blood in your stool is important because it can be a sign of precancerous polyps or colon cancer. Blood vessels at the surface of larger polyps or cancers are often fragile and easily damaged by passing stool. The damaged blood vessels usually release a small amount of blood into the stool, but only rarely is there enough bleeding to be visible in the stool, which is why this test is helpful.
There are many varieties of FIT tests with varying levels of sensitivity, and depending on which you have, it may require as few as one stool sample, instead of three, like other stool sample tests. This test is also less likely to react to bleeding from parts of the upper digestive tract, such as the stomach, which is beneficial in increasing accuracy.
A positive result from the FIT requires follow-up testing. This usually involves direct imaging of the colon and rectum, such as a colonoscopy or sigmoidoscopy.
Please talk to your doctor about which screening is right for you.