From the Guidelines
For colon cancer screening, Cologuard is the preferred option due to its higher sensitivity in detecting cancer and precancerous lesions, despite its higher cost and false positive rate, as evidenced by the most recent study 1. When considering colon cancer screening options, it's essential to weigh the benefits and drawbacks of each test. Cologuard, a multitarget stool DNA test, has been shown to be more sensitive than fecal immunochemical tests (FIT) in detecting cancer and advanced precancerous lesions, with a sensitivity of 92.3% for cancer and 42.4% for advanced lesions 1. In contrast, FIT has a sensitivity of 73.8% for cancer and 23.8% for advanced lesions.
Key Considerations
- Cologuard combines stool DNA testing with hemoglobin immunoassay, making it a more comprehensive screening tool.
- The test is recommended every 3 years, which may be beneficial for individuals who struggle with annual compliance.
- However, Cologuard has a higher false positive rate (13% vs 5% for FIT), which may lead to unnecessary follow-up colonoscopies.
- Cost is another significant consideration, with Cologuard costing approximately $500-600 per test, compared to $20-50 for FIT.
Recommendations
- For average-risk individuals (age 45-75 without family history or symptoms), Cologuard may be the preferred option due to its higher sensitivity and convenience.
- However, FIT may be a better choice for those who prefer annual testing or have cost concerns.
- Both tests require follow-up colonoscopy if positive, and neither replaces colonoscopy for high-risk individuals or those with symptoms, as noted in the study 1.
- The U.S. Multi-Society Task Force on Colorectal Cancer recommends considering the patient's preferences and values when choosing between Cologuard and FIT, as well as the potential benefits and harms of each test 1.
From the Research
Comparison of Cologuard and Fecal Globulin by Immunochemistry
- Cologuard is a multi-target stool DNA test that detects colorectal cancer and advanced adenomas by analyzing stool for human DNA shed from the colon 2.
- Fecal globulin by immunochemistry, also known as fecal immunochemical test (FIT), detects fecal occult blood, which can be an indicator of colorectal cancer or advanced adenomas 3.
Sensitivity and Specificity
- A study comparing the performance of two stool DNA tests and a fecal immunochemical test found that the sensitivity for colorectal cancer of stool DNA test-I, -II, and FIT was 90.5%, 92.9%, and 81.0%, respectively 4.
- The same study found that the specificity of stool DNA test-I, -II, and FIT was 91.4%, 93.3%, and 96.8%, respectively, among those with negative results on colonoscopy 4.
- A meta-analysis found that next-generation multi-target stool DNA test had a sensitivity of 93.6% for detecting colorectal cancer, compared to 71.6% for FIT 5.
- The meta-analysis also found that the specificity of next-generation multi-target stool DNA test was 91.6%, compared to 96.3% for FIT 5.
Diagnostic Efficacy
- A study evaluating the clinical diagnostic value of multi-target stool fecal immunochemical test-DNA (FIT-DNA) test found that it had a high early screening and diagnostic efficacy for colorectal cancer, with a sensitivity of 98.8% and a specificity of 88.9% 6.
- The study also found that the FIT-DNA test had a high negative predictive value of 98.1% for early colorectal cancer and 93.7% for advanced adenoma 6.
Comparison of Cologuard and FIT
- A study found that there was no significant advantage of the two stool DNA tests compared with FIT in detecting colorectal cancer or advanced neoplasms 4.
- However, a meta-analysis found that multi-target stool DNA test had a higher sensitivity for detecting colorectal cancer and advanced precancerous lesions compared to FIT 5.
- Another study found that the mt-sDNA test had a higher sensitivity for detection of CRC and advanced adenomas compared to FIT, but its cost relative to other screening strategies needs to be reduced to be cost-effective 2.