What is more accurate: the Fecal Immunochemical Test (FIT) or Cologuard (Multi-Target Stool DNA test)?

From the Guidelines

Cologuard is generally more accurate than the Fecal Immunochemical Test (FIT) for detecting colorectal cancer, with a higher sensitivity of 92% compared to FIT's 74%. This is because Cologuard combines FIT technology with additional DNA testing to detect genetic mutations associated with colorectal cancer, allowing it to catch more cases 1. However, FIT has a slightly higher specificity of 96% versus Cologuard's 87%, meaning FIT produces fewer false positive results.

Key Considerations

• Cologuard is recommended every three years, while FIT is typically done annually.
• The choice between these tests should consider individual risk factors, cost (FIT is less expensive), and testing frequency preferences.
• Both tests are less invasive alternatives to colonoscopy, which remains the gold standard for colorectal cancer screening.
• Neither test can prevent cancer like colonoscopy can through polyp removal, but both are valuable screening options for detecting cancer early.

Comparison of Tests

• Cologuard: higher sensitivity (92%), lower specificity (87%), recommended every three years.
• FIT: lower sensitivity (74%), higher specificity (96%), typically done annually.

Clinical Implications

• Clinicians should select the colorectal cancer screening test with the patient on the basis of a discussion of benefits, harms, costs, availability, frequency, and patient preferences 1.
• The US Preventive Services Task Force recommends screening for colorectal cancer starting at age 50 years, with various screening tests available, including stool-based tests (FIT, gFOBT, and sDNA-FIT) and direct visualization tests (flexible sigmoidoscopy, colonoscopy, and CT colonography) 1.

From the Research

Comparison of Fecal Immunochemical Test (FIT) and Cologuard (Multi-Target Stool DNA test)

• The Fecal Immunochemical Test (FIT) and Cologuard (Multi-Target Stool DNA test) are two non-invasive screening tests for colorectal cancer.
• Studies have compared the accuracy of these tests, with the Multi-Target Stool DNA test showing higher sensitivity for detecting colorectal cancer, but lower specificity, resulting in a higher false-positive rate 2, 3.
• A study published in 2014 found that the Multi-Target Stool DNA test detected 92.3% of colorectal cancers, compared to 73.8% detected by FIT 3.
• However, the specificity of the Multi-Target Stool DNA test was lower, at 86.6%, compared to 94.9% for FIT 3.
• Another study published in 2022 found that the Multi-Target Stool DNA test had higher sensitivity, but lower specificity, than FIT for detecting colorectal cancer and advanced precancerous lesions 2.
• The choice between FIT and Cologuard may depend on individual patient factors, such as risk level and personal preference, as well as the availability of resources and insurance coverage 4, 2.

Key Findings

• The Multi-Target Stool DNA test has higher sensitivity for detecting colorectal cancer, but lower specificity, resulting in a higher false-positive rate 2, 3.
• FIT has higher specificity, but lower sensitivity, for detecting colorectal cancer 2, 3.
• The Multi-Target Stool DNA test detects more advanced precancerous lesions than FIT 3.
• The cost-effectiveness of the Multi-Target Stool DNA test compared to FIT is still being evaluated 4.

Test Characteristics

• FIT: sensitivity range 73-88%, specificity range 90-96% 5.
• Multi-Target Stool DNA test: sensitivity 92.3%, specificity 86.6% 3.
• The Multi-Target Stool DNA test includes quantitative molecular assays for KRAS mutations, aberrant NDRG4 and BMP3 methylation, and β-actin, plus a hemoglobin immunoassay 3.