At-home stool tests

There are easy-to-use stool tests you can do at home to help find colon cancer. These tests check stools for blood or changes in DNA. They work best for finding cancers that are more advanced, but they also can sometimes find early cancers.

At-home tests can't tell you the stage of the cancer. Stool tests are for detection only. Staging requires imaging and biopsy. The right test for you depends on your age and risk. Be certain to ask your healthcare team which of these options is best for your particular situation.

Available at-home tests include:

• Fecal occult blood tests (FOBTs). These tests should be done once a year for people at average risk. A positive result should always be followed by colonoscopy. There are two types of FOBTs:
  • Fecal immunochemical test (FIT). FIT uses antibodies to detect blood in the stool and offers better accuracy than guaiac-based FOBT (gFOBT). The text is simple. It requires no special diet preparation and has been shown to reduce colon cancer mortality in large studies. After a positive FIT, colonoscopy is needed. If colonoscopy results are typical and you have no symptoms, you can return to screening every 10 years.
  • Guaiac-based FOBT (gFOBT). This test detects blood using a chemical reaction but has lower sensitivity than other tests. It requires a special diet beforehand and is less likely to detect early cancers or polyps. Participation and detection rates are lower than with FIT, making it a less favored option.
• Multitarget stool DNA test (mt-sDNA). The mt-sDNA test checks for both hidden blood and specific DNA changes linked to colon cancer. This test is better than FIT at detecting cancer and advanced precancerous growths. However, it may produce more false positives. This test is approved for average-risk adults age 45 and older and is recommended every 1 to 3 years. If colonoscopy after a positive mt-sDNA test is negative and you have no symptoms, you can return to regular screening every 10 years. One stool DNA test (Cologuard) is approved for colon cancer screening in the United States.
• Multitarget stool RNA test (mt-sRNA). The mt-sRNA test is a newer option that detects RNA markers and blood. It also considers smoking status. It's more sensitive than FIT for both cancer and advanced polyps. Like the mt-sDNA test, the mt-sRNA test may produce more false positives than FIT. This test is approved for average-risk adults age 45 and older and is recommended every three years. Like other stool tests, a positive result should be followed by colonoscopy. If colonoscopy after a positive mt-sRNA test is negative and you have no symptoms, you can return to regular screening every 10 years.