Cologuard Test

The Cologuard test is a non-invasive, stool-based screening test for colorectal cancer and precancerous polyps.

What is the Cologuard test?

The Cologuard test is a molecular test that detects DNA mutations and blood in stool samples. It is designed to identify individuals with colorectal cancer or advanced adenomas, which are precancerous polyps that have a high risk of developing into cancer.

How does the Cologuard test work?

The test involves collecting a stool sample at home using a kit provided by the manufacturer. The sample is then sent to a laboratory for analysis. The test looks for:

• DNA mutations in the KRAS and BMP3 genes, which are commonly found in colorectal cancer and precancerous polyps
• Blood in the stool using an antibody-based assay that detects human hemoglobin
• Methylated DNA markers, including NDRG4 and BMP3, which are associated with colorectal cancer

What are the benefits of the Cologuard test?

The Cologuard test has several benefits, including:

• Non-invasive: The test does not require a colonoscopy or other invasive procedures
• Convenient: The test can be done at home using a stool sample
• Sensitive: The test is sensitive for detecting colorectal cancer and advanced adenomas
• Specific: The test has a high specificity, meaning that it is less likely to produce false positive results

What are the limitations of the Cologuard test?

The Cologuard test has several limitations, including:

• False negatives: The test may not detect all cases of colorectal cancer or precancerous polyps
• False positives: The test may produce false positive results, which can lead to unnecessary follow-up testing and procedures
• Limited sensitivity for early-stage cancer: The test may not be as sensitive for detecting early-stage colorectal cancer

Who should use the Cologuard test?

The Cologuard test is intended for individuals aged 50-85 years who are at average risk for colorectal cancer and have no symptoms or history of colorectal cancer. It is not recommended for individuals with a family history of colorectal cancer, those with a personal history of colorectal cancer or precancerous polyps, or those with symptoms such as bleeding or changes in bowel habits.

What are the next steps after a positive Cologuard test result?

If the Cologuard test result is positive, the individual should undergo a diagnostic colonoscopy to confirm the presence of colorectal cancer or precancerous polyps. A positive result does not necessarily mean that an individual has cancer, but rather that further evaluation is needed.

What are the next steps after a negative Cologuard test result?

If the Cologuard test result is negative, the individual should continue to follow recommended screening guidelines for colorectal cancer. A negative result does not guarantee that an individual does not have colorectal cancer or precancerous polyps, but rather that the test did not detect any abnormalities.