Cologuard vs Colonoscopy

Colon cancer is the third most common type of cancer in the United States. If you are above the age of 45 or 50, doctors recommend that you undergo a colon screening or test to know if you have colon cancer or not. Early testing or screening for colon cancer can help avert severe cases of colon cancer. 

There are different ways with which you can test or screen for colon cancer which include Cologuard and Colonoscopy.

What is Cologuard and how is it done?

Cologuard is a stool-DNA screening test for detecting colon cancer. It is approved by the Food and Drug Administration (FDA). During a Cologuard screening test, changes in your DNA could indicate the presence of colon cancer. The screening checks your DNA for any changes that may indicate the presence of colon cancer. It checks and identifies abnormal DNA and traces of blood that can be caused by precancerous polyps and colon cancer. It also checks for precancerous polyps that may be present in your colon.

Cologuard is less invasive and more convenient than colonoscopy. However, there are some drawbacks too.

How is a Cologuard done?

Before undergoing a Cologuard screening, your doctor will need to order for the screening to be carried out.

A Cologuard follows a certain procedure which includes:

First, you will be given a kit that includes all that you need to collect a stool sample. The kit includes a bracket and collection bucket, a probe and lab tube set.  You will also be given a preservative solution that will preserve your stool sample.

You will use the special bracket and collection bucket to collect samples of your stool inside a toilet. 

You will also use a plastic probe that is enclosed with the kit to collect a swab sample of your stool and place it in a special sterilized tube.

You will then have to pour the preservative solution included in the kit into your stool sample and screw its special lid on tightly.

Your stool sample will then be sent to the lab for testing. 

Precautions

If you have diarrhea or if blood stains are in your stool, you should not provide such sample for testing.

The stool sample must be received at the lab within 72 hours to ensure the integrity of the sample.

Do not drink the preservative liquid enclosed in the collection kit.

After the sample has been received in the lab, the screening test to detect the presence of colorectal cancer will be done.

How is the presence of colon cancer detected?

Your colon shed cells that line the colon every day. Normal cells and also abnormal cells from precancer or cancers are shed into the colon. As your stool passes through the colon, it picks up those cells. 

Cologuard screening is designed to detect the DNA and hemoglobin released from these cells that have been picked up in your stool.

When the result of your test is out, it will be sent to your doctor.

A Cologuard test result either shows a “negative” or a “positive” result. If your result is negative, it indicates that there was no abnormal DNA or hemoglobin found in your stool. If no abnormal DNA or hemoglobin was found in your stool, it means that there’s no suspected presence of colon cancer or precancerous polyps in your colon. 

If your result is positive, it indicates that there were abnormal DNA or hemoglobin found in your stool. If abnormal DNA or hemoglobin were found in your stool, it means that there are suspected presence of colon cancer or precancerous polyps in your colon. 

However, a Cologuard screening test is not 100% accurate. If your result is positive, your doctor may recommend that you undergo a colonoscopy test for a more accurate result. Also, a negative result does not guarantee the absence of colon cancer. You may need to undergo colonoscopy for a more accurate result.

Is Cologuard as good as colonoscopy?

No. Cologuard test results are not 100% accurate.

In fact, false positives results happen in Cologuard tests frequently. Up to 10 percent of positive results from Cologuard test may be incorrect. The rate of false positives increases with age; hence test results should be interpreted with caution in older patients.

Also, a negative Cologuard test result does not guarantee the absence of cancer. If you have a negative Cologuard test result, you will be advised by your doctor to undergo colonoscopy or any other colorectal cancer screening method to confirm your status. 

What is a false positive or negative result?

A false positive result occurs when Cologuard test shows a positive result when a colonoscopy did not find colon cancer or precancerous polyps.

A false negative result occurs when Cologuard test shows a negative result when a colonoscopy identifies the presence of colon cancer or precancerous polyps.

In conclusion, Cologuard is not as good as colonoscopy because colonoscopy identifies more accurate results than Cologuard.

Will Cologuard detect polyps?

Yes. A Cologuard can detect the presence of polyps in your colon through your stool. If your result indicates the presence of abnormal DNA or hemoglobin, it means there are suspected precancerous polyps in your colon. If precancerous polyps are present in your colon, the result of your Cologuard test will be positive.

How accurate is a Cologuard test?

Cologuard results are not 100% accurate. According to studies, 10 percent of positive Cologuard results may be incorrect. False positive results happen frequently and increase with age. 

What is the Cologuard test?

Cologuard test is designed to detect the DNA and hemoglobin released from the cells that have been picked up in your stool.

A Cologuard test either shows a “negative” or a “positive” result. If your result is negative, it indicates that there was no abnormal DNA or hemoglobin found in your stool. If no abnormal DNA or hemoglobin was found in your stool, it means that there’s no suspected colon cancer or precancerous polyps in your colon. 

If your result is positive, it indicates that there were abnormal DNA or hemoglobin found in your stool. If abnormal DNA or hemoglobin were found in your stool, it means that there are suspected presence of colon cancer or precancerous polyps in your colon. 

What should you not eat before Cologuard?

For 72 hours before the test, avoid all types of red meat, beets, broccoli, cantaloupe, carrots, cauliflower, cucumbers, grapefruit, horseradish, mushrooms, radishes, and turnips, melons.

Can hemorrhoids cause a positive Cologuard test?

If you have active bleeding hemorrhoids or any blood condition that may lead to blood in your stool, undergoing a Cologuard test could lead to false positive result.

How much does Cologuard test cost in Dallas, TX & other cities in US?

The cost of Cologuard test is $649. 

What insurance pays for Cologuard vs Colonoscopy?

Cologuard is covered by insurance for colon cancer screen, especially if you are between the ages of 50-75. Cologuard is covered by Medicare and major insurance companies.

Conclusion: Which is Best Colonoscopy or Cologuard?

Cologuard and FIT testing have the benefit of being non-invasive – BUT they miss a LOT of lesions.

Colonoscopy is much more effective to detect lesions.

Also if Cologuard or FIT is positive, then the subsequent colonoscopy that patient requires to check their colon is NO LONGER free.

If colonoscopy is done as the first/screening test – it is FREE for all insurances. Also it allows for the polyp or cancer to be removed/biopsied right away.

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