Colorectal cancer is one of the most common cancers worldwide, but it is also one of the most preventable when detected early. One of the tools used for early detection is the Fecal Immunochemical Test (FIT), a non-invasive test that checks for hidden blood in the stool. This article explores the significance of a positive FIT result and what percentage of positive FIT tests are cancer.
Introduction to FIT (Fecal Immunochemical Test)
The FIT test is primarily used to screen for colorectal cancer by detecting blood in the stool, which may not be visible to the naked eye. It is often recommended for people who are at average risk for colorectal cancer and is typically part of routine screening starting at the age of 50. Unlike the older Fecal Occult Blood Test (FOBT), which required dietary restrictions and multiple stool samples, FIT is more convenient, requiring only one sample and having fewer dietary restrictions.
The primary purpose of the FIT test is to identify individuals who may need further investigation, such as a colonoscopy, to check for cancer or other abnormalities in the colon or rectum. However, a positive FIT result does not always mean cancer.
Understanding Positive FIT Results
A positive FIT result indicates that blood was detected in the stool sample. While this can be a concerning finding, it’s important to understand that blood in the stool can occur for various reasons, and cancer is just one of them.
Common non-cancerous causes of a positive FIT result include:
- Hemorrhoids: Swollen veins in the rectum or anus can cause minor bleeding.
- Polyps: Non-cancerous growths in the colon that may bleed.
- Diverticulosis: Small pouches in the colon wall can cause bleeding.
- Inflammatory bowel disease (IBD): Conditions like Crohn’s disease and ulcerative colitis can result in blood in the stool.
Because of these potential causes, a positive FIT result does not necessarily mean cancer is present. Further testing, such as a colonoscopy, is typically recommended to determine the underlying cause of the bleeding.
Percentage of Positive FIT Results that Indicate Cancer
Research shows that, on average, only a small percentage of people with a positive FIT result are ultimately diagnosed with colorectal cancer. According to studies, about 3-10% of positive FIT results are due to cancer. This percentage can vary depending on factors such as age, family history, and other risk factors.
- Studies from large population-based screenings suggest that about 5% of positive FIT results lead to a diagnosis of colorectal cancer.
- For individuals at average risk, the percentage may be lower, while those with higher risk factors might see a slightly higher percentage.
It’s crucial to remember that while a positive FIT result can be alarming, the test’s purpose is to catch cancer or pre-cancerous conditions early. Early detection significantly improves the chances of successful treatment.
Follow-up After a Positive FIT Result
If you receive a positive FIT result, your healthcare provider will typically recommend a colonoscopy to further investigate the cause of the bleeding. A colonoscopy allows doctors to examine the inside of your colon and rectum for any abnormalities, such as polyps, which can be removed during the procedure.
It’s essential not to panic if your FIT result is positive. While there is a chance that it could indicate cancer, it is more likely to be due to a non-cancerous condition. However, follow-up testing is crucial to rule out cancer or address any other potential issues.
Impact of Early Detection
The importance of early detection in colorectal cancer cannot be overstated. When detected at an early stage, colorectal cancer is highly treatable. The five-year survival rate for people with localized colorectal cancer is about 90%, meaning the cancer has not spread beyond the colon or rectum.
This statistic underscores the value of regular screening and timely follow-up after a positive FIT result. Even if cancer is detected, finding it early gives you the best possible chance for successful treatment and a favorable outcome.
Conclusion
The FIT test plays a crucial role in colorectal cancer screening by detecting hidden blood in the stool, which can be an early sign of cancer. However, a positive FIT result does not automatically mean cancer. Only about 3-10% of positive FIT results are linked to colorectal cancer, with most cases caused by other conditions such as hemorrhoids or polyps.
If you receive a positive FIT result, follow-up testing, such as a colonoscopy, is essential to determine the cause. Early detection through screening tests like FIT can save lives by catching cancer before it has the chance to spread, so regular screening should be an essential part of your health care routine.
By understanding the significance of a positive FIT result and the importance of early detection, you can approach your health screenings with more confidence and take the necessary steps to protect your health.
