What Does a Positive FIT Test Mean?
A Fecal Immunochemical Test (FIT), sometimes called a fecal occult blood test, detects the presence of blood in stool. A positive FIT result indicates that blood has been found. Blood in the stool can be caused by minor issues such as hemorrhoids or polyps. It may also signal the need for further testing to rule out colon cancer.
If you get a positive result on a FIT test, it doesn't automatically mean cancer. However, you should talk to your doctor about additional testing to determine the cause of the bleeding.
What Percentage of Positive FIT Tests Are Cancer?
FIT tests are a popular alternative to screenings like colonoscopy for individuals at average or low risk of developing colon cancer. They are less invasive and time-consuming than standard imaging tests.
While FIT tests are highly effective at detecting the presence of blood in stool, they cannot determine its cause. About 10%–15% of people screened with FIT receive a positive result. However, 96% of those with an abnormal FIT do not receive a cancer diagnosis after a follow-up colonoscopy [1].
A colonoscopy following a positive FIT result can reduce the risk of colon cancer. This procedure can identify potential issues and allow for the removal of precancerous polyps, which may have caused the abnormal FIT result. Removing these polyps helps prevent them from becoming cancerous over time [2].
Why Else Might a FIT Test Be Positive
Blood in stool is often caused by benign conditions. The colon and rectum have millions of tiny blood vessels near the surface, and any irritation or inflammation can cause minor bleeding that may appear in FIT results. Common causes of blood in stool include [3]:
- Diverticulosis — Small pouches in the colon that can bleed
- Inflammatory bowel disease (IBD) — Includes ulcerative colitis and Crohn's disease
- Gastrointestinal ulcers or infections
- Anal fissures
Hemorrhoids, a common cause of both visible and microscopic blood in stool, are often detected by FIT tests. Even if hemorrhoids seem to be the likely cause of bleeding, it's recommended to get follow-up testing to rule out other potential issues.
Next Steps After a Positive FIT Test
If you get a positive FIT result, taking appropriate follow-up steps is crucial.
1. Talk to Your Doctor.
Your doctor will review your medical history, discuss symptoms like recent weight loss or changes in bowel habits, and ask about any family history of colorectal cancer. They will help you decide on the best next steps.
2. Schedule a Colonoscopy.
A colonoscopy is the most effective way to thoroughly examine the colon and remove any precancerous polyps. If no issues are found, you may not need another colonoscopy for up to 10 years. If polyps are detected, you may need to return for a follow-up check within five years or sooner.
3. Stay Proactive with Screening.
Your doctor will recommend the best schedule for future FIT testing. In many cases, FIT screening is advised every one to two years.
Positive FIT Test? You're Not Alone
A positive FIT test can be concerning, but in most cases, it’s not due to cancer—over 90% of people with a positive result don’t have cancer. However, it’s still important to take the next step.
Colonox FIT detects hidden blood in stool, which could be caused by non-cancerous conditions like hemorrhoids, inflammation, or polyps that may need monitoring. The best course of action is to talk to your doctor about scheduling a colonoscopy, which can rule out serious conditions or catch precancerous changes early.
Take a deep breath—a positive FIT result isn’t a diagnosis, just a signal to investigate further.
Key Takeaways
- A positive FIT test does not mean cancer — only 5%-10% of cases lead to a cancer diagnosis.
- Hemorrhoids and other benign conditions can cause blood in stool.
- A follow-up colonoscopy is essential to rule out serious conditions.
- Regular screening helps prevent colorectal cancer.
