Colorectal or colon cancer screening is one of the deadliest types of cancer affecting both men and women. It usually produces symptoms only when the disease has reached an advanced stage. If you are concerned about colon cancer, the best thing you can do is to ask your primary care doctor about colon cancer screening.
Colon cancer screenings can reveal precancerous polyps as well as to detect colon cancer in its early stages when symptoms are unlikely to be present. One of the most commonly used screenings for colon cancer is a stool test.
Let’s find out how accurate stool tests can be.
Stool-Based Test
Our stools hold a lot of information about our health, including the progression of diseases such as colon cancer. There are three types of stool-based tests approved by the Food and Drug Administration:
- Guaiac-based fecal occult blood test (gFOBT)
- Fecal immunochemical test (FIT)
- Multitargeted stool DNA testing (FIT-DNA)
A stool-based test for colon cancer screening involves patients submitting a stool sample for laboratory testing. Each test uses different methods to detect hemoglobin, which is shed by cancerous polyps. The gFOBT uses a type of chemical; the fecal immunochemical test uses antibodies to detect blood in the stool; the FIT-DNA detects not just hemoglobin but also DNA markers.
A stool-based test is less invasive than a colonoscopy and is often preferred by many patients.
Accuracy
Sensitivity measures how often a test correctly generates a positive result for people who are positive for colon cancer, while specificity measures how correctly a test generates a negative result for those who do not have the disease.
A gFOBT has a sensitivity of up to 50 percent and a specificity of almost 80 percent. The disadvantage of the test is that it cannot tell where the bleeding is coming from. The FIT test is more sensitive than the gFOBT test and can detect bleeding from the lower intestine. The FIT has a sensitivity of up to 73 percent and a specificity of up to 94 percent. The FIT-DNA test combines the advantages of FIT and a test for altered DNA, with a 92 percent overall sensitivity and over 99 percent negative predictive value, which means if you test negative, there is a 99.94 percent chance that you do not have colon cancer.
There are advantages and disadvantages to every test, and doctors usually recommend the best option for patients based on several factors.
Patients who receive abnormal results from a stool test for colon cancer screening are usually recommended a colonoscopy. A stool-based test, since it is noninvasive, discreet, and can be performed at home, allows patients to become more proactive with their colorectal health.
Colon Cancer Screening in Brooklyn and Westlake, OH
At North Shore Gastroenterology, we offer life-saving colon cancer screenings for our patients. If you have questions about our screening methods or would like to make an appointment with any of our board-certified gastroenterologists, call (440) 808-1212 or use our convenient online request form. We look forward to your call.
